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Locascio A, Annona G, Caccavale F, D'Aniello S, Agnisola C, Palumbo A. Nitric Oxide Function and Nitric Oxide Synthase Evolution in Aquatic Chordates. Int J Mol Sci 2023; 24:11182. [PMID: 37446358 DOI: 10.3390/ijms241311182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 07/03/2023] [Accepted: 07/04/2023] [Indexed: 07/15/2023] Open
Abstract
Nitric oxide (NO) is a key signaling molecule in almost all organisms and is active in a variety of physiological and pathological processes. Our understanding of the peculiarities and functions of this simple gas has increased considerably by extending studies to non-mammal vertebrates and invertebrates. In this review, we report the nitric oxide synthase (Nos) genes so far characterized in chordates and provide an extensive, detailed, and comparative analysis of the function of NO in the aquatic chordates tunicates, cephalochordates, teleost fishes, and amphibians. This comprehensive set of data adds new elements to our understanding of Nos evolution, from the single gene commonly found in invertebrates to the three genes present in vertebrates.
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Affiliation(s)
- Annamaria Locascio
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy
| | - Giovanni Annona
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy
- Department of Research Infrastructure for Marine Biological Resources (RIMAR), Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy
| | - Filomena Caccavale
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy
| | - Salvatore D'Aniello
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy
| | - Claudio Agnisola
- Department of Biology, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy
| | - Anna Palumbo
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy
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2
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Canosa LF, Bertucci JI. The effect of environmental stressors on growth in fish and its endocrine control. Front Endocrinol (Lausanne) 2023; 14:1109461. [PMID: 37065755 PMCID: PMC10098185 DOI: 10.3389/fendo.2023.1109461] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Accepted: 03/13/2023] [Indexed: 04/03/2023] Open
Abstract
Fish body growth is a trait of major importance for individual survival and reproduction. It has implications in population, ecology, and evolution. Somatic growth is controlled by the GH/IGF endocrine axis and is influenced by nutrition, feeding, and reproductive-regulating hormones as well as abiotic factors such as temperature, oxygen levels, and salinity. Global climate change and anthropogenic pollutants will modify environmental conditions affecting directly or indirectly fish growth performance. In the present review, we offer an overview of somatic growth and its interplay with the feeding regulatory axis and summarize the effects of global warming and the main anthropogenic pollutants on these endocrine axes.
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Affiliation(s)
- Luis Fabián Canosa
- Instituto Tecnológico Chascomús (INTECH), CONICET-EByNT-UNSAM, Chascomús, Argentina
- *Correspondence: Luis Fabián Canosa, ; Juan Ignacio Bertucci,
| | - Juan Ignacio Bertucci
- Centro Oceanográfico de Vigo, Instituto Español de Oceanografía - Consejo Superior de Investigaciones Científicas (IEO-CSIC), Vigo, Spain
- *Correspondence: Luis Fabián Canosa, ; Juan Ignacio Bertucci,
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3
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Bosi G, Maynard BJ, Pironi F, Sayyaf Dezfuli B. Parasites and the neuroendocrine control of fish intestinal function: an ancient struggle between pathogens and host. Parasitology 2022; 149:1842-1861. [PMID: 36076315 PMCID: PMC11010486 DOI: 10.1017/s0031182022001160] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 08/03/2022] [Accepted: 08/11/2022] [Indexed: 12/29/2022]
Abstract
Most individual fish in wild and farmed populations can be infected with parasites. Fish intestines can harbour protozoans, myxozoans and helminths, which include several species of digeneans, cestodes, nematodes and acanthocephalans. Enteric parasites often induce inflammation of the intestine; the pathogen provokes changes in the host physiology, which will be genetically selected for if they benefit the parasite. The host response to intestinal parasites involves neural, endocrine and immune systems and interaction among these systems is coordinated by hormones, chemokines, cytokines and neurotransmitters including peptides. Intestinal fish parasites have effects on the components of the enteric nervous and endocrine systems; mechanical/chemical changes impair the activity of these systems, including gut motility and digestion. Investigations on the role of the neuroendocrine system in response to fish intestinal parasites are very few. This paper provides immunohistochemical and ultrastructural data on effects of parasites on the enteric nervous system and the enteric endocrine system in several fish–parasite systems. Emphasis is on the occurrence of 21 molecules including cholecystokinin-8, neuropeptide Y, enkephalins, galanin, vasoactive intestinal peptide and serotonin in infected tissues.
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Affiliation(s)
- Giampaolo Bosi
- Department of Veterinary Medicine and Animal Science, University of Milan, St. dell'Università 6, 26900 Lodi, Italy
| | - Barbara J. Maynard
- The Institute for Learning and Teaching, Colorado State University, Fort Collins, CO 80523, USA
| | - Flavio Pironi
- Department of Life Sciences and Biotechnology, University of Ferrara, St. Borsari 46, 44121 Ferrara, Italy
| | - Bahram Sayyaf Dezfuli
- Department of Life Sciences and Biotechnology, University of Ferrara, St. Borsari 46, 44121 Ferrara, Italy
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4
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Ceccotti C, Giaroni C, Bistoletti M, Viola M, Crema F, Terova G. Neurochemical characterization of myenteric neurons in the juvenile gilthead sea bream (Sparus aurata) intestine. PLoS One 2018; 13:e0201760. [PMID: 30075006 PMCID: PMC6075763 DOI: 10.1371/journal.pone.0201760] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 07/20/2018] [Indexed: 12/12/2022] Open
Abstract
We evaluated the chemical coding of the myenteric plexus in the proximal and distal intestine of gilthead sea bream (Sparus aurata), which represents one of the most farmed fish in the Mediterranean area. The presence of nitric oxide (NO), acetylcholine (ACh), serotonin (5-HT), calcitonin-gene-related peptide (CGRP), substance P (SP) and vasoactive intestinal peptide (VIP) containing neurons, was investigated in intestinal whole mount preparations of the longitudinal muscle with attached the myenteric plexus (LMMP) by means of immunohistochemical fluorescence staining. The main excitatory and inhibitory neurochemicals identified in intestinal smooth muscle were ACh, SP, 5HT, and NO, VIP, CGRP. Some neurons displayed morphological features of ascending and descending interneurons and of putative sensory neurons. The expression of these pathways in the two intestinal regions is largely superimposable, although some differences emerged, which may be relevant to the morphological properties of each region. The most important variances are the higher neuronal density and soma size in the proximal intestine, which may depend on the volume of the target tissue. Since in the fish gut the submucosal plexus is less developed, myenteric neurons substantially innervate also the submucosal and epithelial layers, which display a major thickness and surface in the proximal intestine. In addition, myenteric neurons containing ACh and SP, which mainly represent excitatory motor neurons and interneurons innervating the smooth muscle were more numerous in the distal intestine, possibly to sustain motility in the thicker smooth muscle coat. Overall, this study expands our knowledge of the intrinsic innervation that regulates intestinal secretion, absorption and motility in gilthead sea bream and provides useful background information for rational design of functional feeds aimed at improving fish gut health.
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Affiliation(s)
- Chiara Ceccotti
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
| | - Cristina Giaroni
- Department of Medicine and Surgery, University of Insubria, Varese, Italy
| | - Michela Bistoletti
- Department of Medicine and Surgery, University of Insubria, Varese, Italy
| | - Manuela Viola
- Department of Medicine and Surgery, University of Insubria, Varese, Italy
| | - Francesca Crema
- Department of Internal Medicine and Therapeutics, Section of Pharmacology, University of Pavia, Pavia, Italy
| | - Genciana Terova
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
- Inter-University Centre for Research in Protein Biotechnologies "The Protein Factory"- Polytechnic University of Milan and University of Insubria, Varese, Italy
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5
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Volkoff H. The Neuroendocrine Regulation of Food Intake in Fish: A Review of Current Knowledge. Front Neurosci 2016; 10:540. [PMID: 27965528 PMCID: PMC5126056 DOI: 10.3389/fnins.2016.00540] [Citation(s) in RCA: 164] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 11/07/2016] [Indexed: 12/14/2022] Open
Abstract
Fish are the most diversified group of vertebrates and, although progress has been made in the past years, only relatively few fish species have been examined to date, with regards to the endocrine regulation of feeding in fish. In fish, as in mammals, feeding behavior is ultimately regulated by central effectors within feeding centers of the brain, which receive and process information from endocrine signals from both brain and peripheral tissues. Although basic endocrine mechanisms regulating feeding appear to be conserved among vertebrates, major physiological differences between fish and mammals and the diversity of fish, in particular in regard to feeding habits, digestive tract anatomy and physiology, suggest the existence of fish- and species-specific regulating mechanisms. This review provides an overview of hormones known to regulate food intake in fish, emphasizing on major hormones and the main fish groups studied to date.
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Affiliation(s)
- Helene Volkoff
- Departments of Biology and Biochemistry, Memorial University of NewfoundlandSt. John's, NL, Canada
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Pirone A, Ding BA, Giannessi E, Coli A, Stornelli MR, di Cossato MMF, Piano I, Lenzi C. Glucagon-like peptide 1 (GLP-1) in the gastrointestinal tract of the pheasant (Phasianus colchicus). Acta Histochem 2012; 114:535-9. [PMID: 22036174 DOI: 10.1016/j.acthis.2011.10.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Revised: 10/07/2011] [Accepted: 10/09/2011] [Indexed: 12/25/2022]
Abstract
The distribution of Glucagon-like peptide 1 (GLP-1) was investigated in the gastrointestinal tract of the pheasant using immunohistochemistry. GLP-1 immunoreactive cells were common in the small intestine, in the proventriculus and in the pancreas. Immunostained cells were not seen in the crop, in the gizzard and in the large intestine. Double labelling demonstrated that GLP-1 and pituitary adenylate cyclase-activating polypeptide (PACAP) were occasionally co-localized only in the duodenal villi. In contrast to what was previously described in the chicken and ostrich, we noted GLP-1 positive cells in the duodenum. These data were consistent with the presence of proglucagon mRNA in the chicken duodenum. Our findings indicate that GLP-1 might have an inhibitory effect on gastric and crop emptying and on acid secretion also in the pheasant. Moreover, the results of the present research regarding the initial region of the small intestine suggest a further direct mechanism of the GLP-1 release during the early digestion phase and an enhancement of its incretin role.
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7
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Pirone A, Baoan D, Piano I, Santina LD, Baglini A, Lenzi C. Pituitary adenylate cyclase-activating peptide (PACAP) immunoreactivity distribution in the small intestine of the adult New Hampshire chicken. Acta Histochem 2011; 113:477-83. [PMID: 20598353 DOI: 10.1016/j.acthis.2010.04.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2010] [Revised: 04/25/2010] [Accepted: 04/26/2010] [Indexed: 11/25/2022]
Abstract
We conducted a study in which we demonstrated by means of immunoperoxidase and immunofluorescence methods the presence of pituitary adenylate cyclase-activating peptide 38 (PACAP-38) immunoreactivity in the small intestine of adult New Hampshire chickens and its co-localization with VIP. In particular we describe for the first time the presence of PACAP-positive cells in the epithelium of crypts and villi. Using double immunostaining, we observed that these two peptides were widely co-localized in the nerve structures of duodenum and jejunum with the exception of the ileum, where we noticed a faint co-localization regarding the nerve fibers of the lamina propria of the villi. Furthermore, the two peptides were occasionally co-stored in the epithelial cells of the mucosa. Our findings suggest that in the chicken small intestine, PACAP can be considered, not only as a neuromodulator released by nerve elements, but also as a gut hormone secreted by endocrine cells, and it appears likely to have a role in the regulation of important intestinal physiological functions.
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Olsson C, Holmgren S. Autonomic control of gut motility: a comparative view. Auton Neurosci 2010; 165:80-101. [PMID: 20724224 DOI: 10.1016/j.autneu.2010.07.002] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2010] [Revised: 06/24/2010] [Accepted: 07/06/2010] [Indexed: 12/16/2022]
Abstract
Gut motility is regulated to optimize food transport and processing. The autonomic innervation of the gut generally includes extrinsic cranial and spinal autonomic nerves. It also comprises the nerves contained entirely within the gut wall, i.e. the enteric nervous system. The extrinsic and enteric nervous control follows a similar pattern throughout the vertebrate groups. However, differences are common and may occur between groups and families as well as between closely related species. In this review, we give an overview of the distribution and effects of common neurotransmitters in the vertebrate gut. While the focus is on birds, reptiles, amphibians and fish, mammalian data are included to form the background for comparisons. While some transmitters, like acetylcholine and nitric oxide, show similar distribution patterns and effects in most species investigated, the role of others is more varying. The significance for these differences is not yet fully understood, emphasizing the need for continued comparative studies of autonomic control.
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Affiliation(s)
- Catharina Olsson
- Department of Zoology/Zoophysiology, University of Gothenburg, Sweden.
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9
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Chang JP, Sawisky GR, Mitchell G, Uretsky AD, Kwong P, Grey CL, Meints AN, Booth M. PACAP stimulation of maturational gonadotropin secretion in goldfish involves extracellular signal-regulated kinase, but not nitric oxide or guanylate cyclase, signaling. Gen Comp Endocrinol 2010; 165:127-35. [PMID: 19539623 DOI: 10.1016/j.ygcen.2009.06.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2009] [Revised: 06/02/2009] [Accepted: 06/12/2009] [Indexed: 10/20/2022]
Abstract
In goldfish, nitric oxide synthase (NOS) immunoreactivity is present in gonadotropes and extracellular signal-regulated protein kinase (ERK) mediates GnRH stimulation of gonadotropin release and synthesis. In this study, we tested the possible involvement of nitric oxide (NO) and ERK in mediating PACAP-stimulated maturational gonadotropin (GTH-II) release from primary cultures of dispersed goldfish pituitary cells. In static incubation experiments, PACAP-induced GTH-II release was unaffected by two inhibitors of NOS synthase, AGH and 1400W; whereas addition of a NO donor, SNAP, elevated GTH-II secretion. In perifusion experiments, neither NOS inhibitors (AGH, 1400W and 7-Ni) nor NO scavengers (PTIO and rutin hydrate) attenuated the GTH-II response to pulse applications of PACAP. In addition, the GTH-II responses to PACAP and the NO donor SNP were additive while PTIO blocked SNP action. Although dibutyryl cGMP increased GTH-II secretion in static incubation, inhibition of guanylate cyclase (GC), a known down-stream target for NO signaling, did not reduce the GTH-II response to pulse application of PACAP. On the other hand, GTH-II responses to PACAP in perifusion were attenuated in the presence of two inhibitors of ERK kinase (MEK), U 0126 and PD 98059. These results suggest that although increased availability of NO and cGMP can lead to increased GTH-II secretion, MEK/ERK signaling, rather than NOS/NO/GC activation, mediates PACAP action on GTH-II release in goldfish.
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Affiliation(s)
- John P Chang
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
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10
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The enteric nervous system. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/s1546-5098(10)03008-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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11
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Gräns A, Albertsson F, Axelsson M, Olsson C. Postprandial changes in enteric electrical activity and gut blood flow in rainbow trout (Oncorhynchus mykiss) acclimated to different temperatures. ACTA ACUST UNITED AC 2009; 212:2550-7. [PMID: 19648399 DOI: 10.1242/jeb.030593] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Enteric electrical activity, cardiac output and gut blood flow were measured in rainbow trout (Oncorhynchus mykiss) acclimated to either 10 degrees C or 16 degrees C. Enteric electrical activity showed, in both the fasted and postprandial state, a distinct pattern with clusters of burst-like events interspersed by silent periods. The frequency of electrical events increased postprandially for both acclimation groups. Event frequency increased from 3.0+/-0.5 to 9.6+/-1.4 events min(-1) and from 5.9+/-0.9 to 11.8+/-2.0 events min(-1) in the 10 degrees C and 16 degrees C groups, respectively. Similarly, the number of events per cluster increased postprandially for both acclimation groups. Gut blood flow, cardiac output and heart rate increased after feeding. The gut blood flow significantly increased in both groups and peaked at 257+/-19% and 236+/-22% in the 10 degrees C and 16 degrees C groups, respectively. There was a strong correlation between the number of events and gut blood flow at both temperatures. Comparison between the two groups showed that fish acclimated to 16 degrees C may have an increased cost of sustaining the basal activity of the gut compared with the group acclimated to 10 degrees C. In conclusion, we have for the first time measured enteric electrical activity in vivo in a fish species and we have also demonstrated a strong correlation between gut blood flow and enteric electrical activity in fasted and postprandial fish.
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Affiliation(s)
- Albin Gräns
- Department of Zoology, University of Gothenburg, Göteborg, Sweden.
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12
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Vaudry D, Falluel-Morel A, Bourgault S, Basille M, Burel D, Wurtz O, Fournier A, Chow BKC, Hashimoto H, Galas L, Vaudry H. Pituitary Adenylate Cyclase-Activating Polypeptide and Its Receptors: 20 Years after the Discovery. Pharmacol Rev 2009; 61:283-357. [DOI: 10.1124/pr.109.001370] [Citation(s) in RCA: 829] [Impact Index Per Article: 55.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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13
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Abstract
The enteric nervous system follows a similar overall arrangement in all vertebrate groups. In fish, the majority of nerve cell bodies are found in the myenteric plexus, innervating muscles, blood vessels and glands. In this review, I describe similarities and differences in size, shape and transmitter content in enteric neurons in different fish species and also in comparison with other vertebrates, foremost mammals. The use of different histological and immunochemical methods is reviewed in a historical perspective including advantages and disadvantages of different methods. Lately, zebrafish have become an important model species for developmental studies of the nervous system, including the enteric nervous system, and this is briefly discussed. Finally, examples of how the enteric nervous system controls gut activity in fish is presented, focussing on the effect on gastrointestinal motility.
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Xu M, Volkoff H. Cloning, tissue distribution and effects of food deprivation on pituitary adenylate cyclase activating polypeptide (PACAP)/PACAP-related peptide (PRP) and preprosomatostatin 1 (PPSS 1) in Atlantic cod (Gadus morhua). Peptides 2009; 30:766-76. [PMID: 19135491 DOI: 10.1016/j.peptides.2008.12.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2008] [Revised: 12/09/2008] [Accepted: 12/09/2008] [Indexed: 10/21/2022]
Abstract
Full-length complementary deoxyribonucleic acid sequences encoding pituitary adenylate cyclase activating polypeptide (PACAP)/PACAP-related peptide (PRP) and preprosomatostatin 1 (PPSS 1) were cloned from Atlantic cod (Gadus morhua) hypothalamus using reverse transcription and rapid amplification of complementary deoxyribonucleic acid ends. Semi-quantitative reverse transcriptase polymerase chain reaction shows that PRP/PACAP mRNA and PPSS 1 mRNA are widely distributed throughout cod brain. During development, PRP/PACAP and PPSS 1 were detected at the 30-somite stage and pre-hatching stage, respectively, and expression levels gradually increased up to the hatched larvae. PPSS 1, but not PRP/PACAP, appeared to be affected by food availability during early development. In juvenile cod, PPSS 1 expression levels increased and remained significantly higher than that of control fed fish throughout 30 days of starvation and during a subsequent 10 days refeeding period. In contrast, PRP/PACAP expression levels were not affected by 30 days of food deprivation, but a significant increase in expression levels was observed during the 10 days refeeding period in the experimental food-deprived group as compared to the control fed group. Our results suggest that PRP/PACAP and PPSS 1 may be involved in the complex regulation of growth, feeding and metabolism during food deprivation and refeeding in Atlantic cod.
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Affiliation(s)
- Meiyu Xu
- Departments of Biology, Memorial University of Newfoundland, St John's, Canada.
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15
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Distribution and neurotransmitter localization in the heart of the ray-finned fish, bichir (Polypterus bichir bichir Geoffroy St. Hilaire, 1802). Acta Histochem 2009; 111:93-103. [PMID: 18805572 DOI: 10.1016/j.acthis.2008.05.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2008] [Revised: 04/29/2008] [Accepted: 05/07/2008] [Indexed: 11/20/2022]
Abstract
Anatomical and physiological studies of cardiovascular control are lacking in the ray-finned fish, the bichirs. The present immunohistochemical studies on the bichir (Polypterus bichir bichir) demonstrated the occurrence of intracardiac neurons and nerve fibers in the heart. Immunoreactivity to tyrosine hydroxylase (TH) and acetylcholinesterase (AchE) and various neuropeptides (substance P, galanin, vasoactive intestinal polypeptide (VIP) and pituitary adenylate cyclase-activating peptide (PACAP)), including neuronal nitric oxide synthase (nNOS), was found in the nerve cell bodies lying close to the Sinus venosus and the sino-atrial region. The main intracardiac localization of the nervous tissue is a network of nerve fibers, presumably corresponding to the postganglionic outflow giving rise to nerve terminals and the nerve cell bodies. In addition, the heart is innervated by extrinsic monoamine-containing nerve fibers supplying the Conus arteriosus and Sinus venosus, and substance P and galanin immunopositive fibers probably originating from cranial and spinal ganglia. The adrenergic innervation of the heart of the bichir is similar to that of the teleosts, but further studies are required on nervous control of the heart.
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Zaitseva OV, Kuznetsova TV, Markosova TG. NADPH-diaphorase activity in the digestive system of gastropod molluscs Achatina fulica and Littorina littorea. J EVOL BIOCHEM PHYS+ 2009. [DOI: 10.1134/s002209300901013x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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17
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Holmgren S, Olsson C. Chapter 10 The Neuronal and Endocrine Regulation of Gut Function. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/s1546-5098(09)28010-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
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18
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Huang WT, Li CJ, Wu PJ, Chang YS, Lee TL, Weng CF. Expression and in vitro regulation of pituitary adenylate cyclase-activating polypeptide (pacap38) and its type I receptor (pac1-r) in the gonads of tilapia (Oreochromis mossambicus). Reproduction 2008; 137:449-67. [PMID: 19106203 DOI: 10.1530/rep-08-0422] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Pituitary adenylate cyclase-activating polypeptide (PACAP), a pleiotropic neuropeptide, has diverse functions in mammals. However, studies of the expression and function of PACAP and its receptor in fish, particularly in the reproductive system, are still limited. In this report, semi-quantitative RT-PCR and immunohistochemical staining were performed to identify expression domains of commercially important tilapia (Oreochromis mossambicus). PACAP (tpacap(38)) and its type I receptor (tpac(1)-r). Transcripts were detected in the brain, gallbladder, gill, heart, intestine, kidney, muscles, pancreas, spleen, stomach, testes, and ovaries, but not in the liver. Expression of tpacap(38) and tpac(1)-r mRNA in brain tissue was significantly higher in both sexes compared with other tissues. Addition of exogenous ovine PACAP(38) (0.25-5 nM), cAMP analog (dibutyryl-cAMP, 0.25-1.5 mM) or forskolin (adenylate cyclase activator, 1-10 microM) significantly upregulated tpacap(38) in the gonads via a dose- and time-dependent fashion. This effect reached a maximal level at 2 h after induction, and then decreased with prolonged culture for up to 4 or 8 h. Additionally, the expression levels of tpac(1)-r were not significantly affected by ovine PACAP(38) or dibutyryl-cAMP in either sex. Forskolin had a slightly inductive effect and its function could be suppressed with the addition of protein kinase A (PKA) inhibitor, H89 (10 microM), indicating involvement of the cAMP-PKA signaling pathway in the regulation of tpacap(38). Expression of tpacap(38) and tpac(1)-r in the gonads of tilapia suggests that PACAP may mediate gonadotropin action via paracrine/autocrine mechanisms in this bony fish.
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Affiliation(s)
- Wei-Tung Huang
- Department of Molecular Biotechnology, Da-Yeh University, Chang-Hua 515, Taiwan, ROC.
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19
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Olsson C, Holmberg A, Holmgren S. Development of enteric and vagal innervation of the zebrafish (Danio rerio) gut. J Comp Neurol 2008; 508:756-70. [PMID: 18393294 DOI: 10.1002/cne.21705] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The autonomic nervous system develops following migration and differentiation of precursor cells originating in the neural crest. Using immunohistochemistry on intact zebrafish embryos and larvae we followed the development of the intrinsic enteric and extrinsic vagal innervation of the gut. At 3 days postfertilization (dpf), enteric nerve cell bodies and fibers were seen mainly in the middle and distal intestine, while the innervation of the proximal intestine was scarcer. The number of fibers and cell bodies gradually increased, although a large intraindividual variation was seen in the timing (but not the order) of development. At 11-13 dpf most of the proximal intestine received a similar degree of innervation as the rest of the gut. The main intestinal branches of the vagus were similarly often already well developed at 3 dpf, entering the gut at the transition between the proximal and middle intestine and projecting posteriorly along the length of the gut. Subsequently, fibers branching off the vagus innervated all regions of the gut. The presence of several putative enteric neurotransmitters was suggested by using markers for neurokinin A (NKA), pituitary adenylate cyclase-activating polypeptide (PACAP), vasoactive intestinal polypeptide (VIP), nitric oxide, serotonin (5-hydroxytryptamine, 5-HT), and calcitonin gene-related peptide (CGRP). The present results corroborate the belief that the enteric innervation is well developed before the onset of feeding (normally occurring around 5-6 dpf). Further, the more detailed picture of how development proceeds at stages previously not examined suggests a correlation between increasing innervation and more regular and elaborated motility patterns.
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Affiliation(s)
- Catharina Olsson
- Department of Zoology/Zoophysiology, University of Gothenburg, Göteborg, Sweden.
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Holmberg A, Olsson C, Holmgren S. The effects of endogenous and exogenous nitric oxide on gut motility in zebrafish Danio rerio embryos and larvae. J Exp Biol 2006; 209:2472-9. [PMID: 16788030 DOI: 10.1242/jeb.02272] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Using motion analysis, the ontogeny of the nitrergic control system in the gut was studied in vivo in zebrafish Danio rerio embryos and larvae. For the first time we show the presence of a nitrergic tonus,modulating both anterograde and retrograde contraction waves in the intestine of developing zebrafish. At 4 d.p.f. (days post fertilisation), the nitric oxide synthase (NOS) inhibitor l-NAME (three boluses of 50–100 nl, 10–3 mol l–1) increased the anterograde contraction wave frequency by 0.50±0.10 cycles min–1. Subsequent application of the NO donor sodium nitroprusside (SNP; three boluses of 50–100 nl, 10–4mol l–1) reduced the frequency of propagating anterograde waves (–0.71±0.20 cycles min–1). This coincided with the first appearance of an excitatory cholinergic tonus, observed in an earlier study. One day later, at 5 d.p.f., in addition to the effect on anterograde contraction waves, application of l-NAME increased(0.39±0.15 cycles min–1) and following SNP application reduced (–1.61±0.36 cycles min–1) the retrograde contraction wave frequency. In contrast, at 3 d.p.f., when no spontaneous motility is observed, application of l-NAME did not induce contraction waves in either part of the gut, indicating the lack of a functional inhibitory tonus at this early stage. Gut neurons expressing NOS-like immunoreactivity were present in the distal and middle intestine as early as 2 d.p.f., and at 1 day later in the proximal intestine. In conclusion, the present study suggests that a nitrergic inhibitory tonus develops shortly before or at the time for onset of exogenous feeding.
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Affiliation(s)
- Anna Holmberg
- Department of Zoophysiology, Göteborg University, Box 463, SE 405 30 Göteborg, Sweden.
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Matsuda K, Nagano Y, Uchiyama M, Onoue S, Takahashi A, Kawauchi H, Shioda S. Pituitary adenylate cyclase-activating polypeptide (PACAP)-like immunoreactivity in the brain of a teleost, Uranoscopus japonicus: immunohistochemical relationship between PACAP and adenohypophysial hormones. ACTA ACUST UNITED AC 2005; 126:129-36. [PMID: 15620426 DOI: 10.1016/j.regpep.2004.08.019] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) could play a role in stimulating pituitary hormone release in fish brain. In this study, we used immunochemical techniques to examine the histological and quantitative distribution of PACAP in the central nervous system (CNS) of a teleost, the stargazer, Uranoscopus japonicus. In addition, high performance liquid chromatographic (HPLC) analysis was performed to characterize the form of PACAP present, while the relationship between PACAP and adenohypophysial hormones was also determined immunohistochemically. PACAP-like immunoreactive (LI) neuronal cell bodies and fibers were found not only in the hypothalamo-pituitary region but also in the midbrain and hindbrain regions. PACAP-LI fibers were identified in the neurohypophysis in close proximity to pituitary cells containing immunoreactive hormones such as somatolactin, the N-terminal peptide of proopiomelanocortin, and N-acetyl endorphin. The concentration of immunoreactive PACAP in whole brain tissue was approximately 300 pmol/g wet weight. The average concentrations of immunoreactive PACAP in regions of the telencephalon, diencephalon, tectum, cerebellum, and rhombencephalon were 217.53, 510.26, 83.30, 148.64, and 364.62 pmol/g, respectively. In reverse-phase HPLC experiments, the predominant form of immunoreactive PACAP eluted closely with synthetic stargazer PACAP38, while PACAP27-like immunoreactivity was negligible. These results suggest that PACAP38 is the predominant PACAP form in the stargazer CNS, and that PACAP acts not only as a hypophysiotropic factor for adenohypophysial hormone release but also as a neurotransmitter and neuromodulator in the CNS.
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Affiliation(s)
- Kouhei Matsuda
- Department of Biology, Faculty of Science, Toyama University, 3190-Gofuku, Toyama, Toyama 930-8555, Japan.
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Buddington RK, Krogdahl A. Hormonal regulation of the fish gastrointestinal tract. Comp Biochem Physiol A Mol Integr Physiol 2004; 139:261-71. [PMID: 15556381 DOI: 10.1016/j.cbpb.2004.09.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2004] [Revised: 08/18/2004] [Accepted: 09/06/2004] [Indexed: 10/26/2022]
Abstract
The gastrointestinal tracts (GIT) of fish and other vertebrates are challenged with a diversity of functional demands caused by changes and differences in dietary inputs and environmental conditions. This contribution reviews how hormonal regulation plays an essential role in modulating the GIT functions of fish to match changes in functional demands. Exemplary is how hormones produced by the GIT, the associated organs (e.g., pancreas), and other sources (e.g., hypothalamus, adrenal cortex, thyroid, gonads) modulate the digestive processes (motility, secretion, and nutrient absorption) in response to dietary inputs. Hormones regulate the other GIT functions of osmoregulation (secretion and absorption of electrolytes and water), immunity, endocrine secretions, metabolism, and the elimination of toxic metabolites and environmental contaminants to match changes in environmental conditions and physiological states. Although the regulatory molecules and associated signaling pathways have been conserved during evolution of the vertebrate GIT, the specific responses often vary among fish with different feeding habits and from different environments, and can differ from those described for mammals.
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Affiliation(s)
- Randal K Buddington
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS 39762, USA.
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Holmberg A, Schwerte T, Pelster B, Holmgren S. Ontogeny of the gut motility control system in zebrafish Danio rerio embryos and larvae. J Exp Biol 2004; 207:4085-94. [PMID: 15498954 DOI: 10.1242/jeb.01260] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Using digital motion analysis, the ontogeny of the cholinergic, tachykinin and pituitary adenylate cyclase-activating polypeptide (PACAP) control systems was studied in zebrafish Danio rerio larvae, in vivo. For the first time we show that the regular propagating anterograde waves that occur in the zebrafish larval gut before and around the onset [at 5–6 days post fertilization (d.p.f.)] of feeding are modulated by acetylcholine or atropine, PACAP and NKA (neurokinin A). At 3 d.p.f., when no spontaneous motility has developed, application of acetylcholine did not affect the gut. However, at 4 d.p.f., acetylcholine increased and atropine reduced the frequency of propagating anterograde waves. At 5 d.p.f., NKA increased and PACAP reduced the wave frequency. This suggests that both excitatory and inhibitory pathways develop at an early stage in the gut, independent of exogenous feeding. Immunohistochemistry established the presence of gut neurons expressing PACAP and NKA in the proximal part of the developing gut from the first stage investigated (2 d.p.f.) and before regular motility was observed. 1 d.p.f. (PACAP) or 2 d.p.f. (NKA) stages later the whole gut was innervated. This supports physiological results that gut motility is under neuronal control during the period when regular motility patterns develop.
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Affiliation(s)
- Anna Holmberg
- Department of Zoophysiology, Göteborg University, Box 463, SE 405 30 Göteborg, Sweden
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Zaccone G, Ainis L, Mauceri A, Lo Cascio P, Lo Giudice F, Fasulo S. NANC nerves in the respiratory air sac and branchial vasculature of the Indian catfish, Heteropneustes fossilis. Acta Histochem 2004; 105:151-63. [PMID: 12831167 DOI: 10.1078/0065-1281-00695] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Gill and air sac of the Indian catfish Heteropneustes fossilis harbour a nerve network comprising an innervated system of neuroepithelial endocrine cells; the latter cells are found especially in the gill. A series of antibodies was used for the immunohistochemical detection of neurotransmitters of the neural non-adrenergic, non-cholinergic (NANC) systems such as the sensory neuropeptides (enkephalins), the inhibitory neuropeptide VIP and neuronal nitric oxide synthase (nNOS) responsible for nitric oxide (NO) production which is an inhibitory NANC neurotransmitter. NADPH-diaphorase (NADPH-d) histochemistry was used as marker of nNOS although it is not a specific indicator of constitutively-expressed NOS in gill and air sac tissues. A tyrosine hydroxylase antibody was used to investigate adrenergic innervation. Nitrergic and VIP-positive sensory innervation was found to be shared by gill and air sac. Immunohistochemistry revealed the presence of enkephalins, VIP, NOS and NADPH-d in nerves associated with branchial and air sac vasculature, and in the neuroendocrine cell systems of the gill. Adrenergic nerve fibers were found in some parts of the air sac vasculature. The origin of the nerve fibers remains unclear despite previous findings showing the presence of both NADPH-d and nNOS in the sensory system of the glossopharyngeal and vagus nerves including the branchial structure. Scarce faintly stained nNOS-positive neurons were located in the gill but were never detected in the air sac. These findings lead to the conclusion that a postganglionic innervation of the airways is absent. Mucous goblet cells in the gill were found to express nNOS and those located in the non-respiratory interlamellar areas of the air sac were densely innervated by nNOS-positive and VIP-positive nerve fibers. Our immunohistochemical studies demonstrate that most arteries of the gill and air sac share a NANC (basically nitrergic) innervation which strongly suggests that they are homologous structures.
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Affiliation(s)
- Giacomo Zaccone
- Department of Animal Biology and Marine Ecology, Faculty of Science, University of Messina, Italy.
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Badawy G, Reinecke M. Ontogeny of the VIP system in the gastro-intestinal tract of the Axolotl, Ambystoma mexicanum: successive appearance of co-existing PACAP and NOS. ANATOMY AND EMBRYOLOGY 2003; 206:319-25. [PMID: 12649730 DOI: 10.1007/s00429-002-0294-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/31/2002] [Indexed: 11/29/2022]
Abstract
Evidence for the presence and potential co-existence of vasoactive intestinal polypeptide (VIP), pituitary adenylate cyclase-activating polypeptide (PACAP) and nitric oxide synthase (NOS) in gastro-intestinal endocrine cells and/or nerve fibers is conflicting and very few results exist on development. This immunofluorescence study aims to clarify the appearance and localization of VIP, PACAP and NOS in the gastro-intestinal tract of the Axolotl, Ambystoma mexicanum, during ontogeny. VIP-immunoreactivity appeared in nerve fibers as early as on day 3 after hatching likely indicating a particular role, such as a trophic action, of VIP in very early development. PACAP-immunoreactivity was observed 3 days later within the VIP-immunoreactive (-IR) fibers. From this time on, VIP- and PACAP-immunoreactivity exhibited complete co-existence. VIP/PACAP-IR fibers were found throughout the gastro-intestinal tract. They were most prominent in the myenteric plexus and the muscle layers and less frequent in the submucosa. NOS-immunoreactivity appeared as late as at the 1st (64 days) juvenile stage in a subpopulation of the VIP/PACAP-IR fibers that contacted submucosal arteries. We found only very few VIP/PACAP-IR perikarya, indicating that part of the VIP/PACAP-IR fibers is of extrinsic origin. On day 12 and in the 1st and 2nd (104 days) juvenile stage, infrequent PACAP-IR entero-endocrine cells were noted, while neither VIP- nor NOS-immunoreactivity occurred in endocrine cells at any stage of development. The complete coexistence of neuronal PACAP- and VIP-immunoreactivities and their very early appearance in ontogeny may suggest important and coordinated roles of both peptides in the control of Axolotl gastro-intestinal activity, while the VIP/ PACAP/NOS-IR fibers may be involved in the regulation of submucosal blood flow.
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Affiliation(s)
- Gamal Badawy
- School of Biosciences, University of Birmingham, Birmingham, UK
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Adams BA, Lescheid DW, Vickers ED, Crim LW, Sherwood NM. Pituitary adenylate cyclase-activating polypeptide and growth hormone-releasing hormone-like peptide in sturgeon, whitefish, grayling, flounder and halibut: cDNA sequence, exon skipping and evolution. REGULATORY PEPTIDES 2002; 109:27-37. [PMID: 12409211 DOI: 10.1016/s0167-0115(02)00167-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To better understand the evolution of pituitary adenylate cyclase-activating polypeptide (PACAP) and growth hormone-releasing hormone (GHRH), we isolated the cDNAs encoding these peptides from the brains of five species of fish: sturgeon, whitefish, grayling, flounder and halibut. Both hormones are encoded in tandem in full-length cDNAs. We compared the phylogenetic relationship among these and other known sequences encoding PACAP. In closely related species, transcripts encoding PACAP and GHRH are strongly conserved in the hormone coding regions, moderately conserved in the signal peptide, cryptic peptide and 3'-untranslated regions, but are most varied in the 5'-untranslated regions.Next, we compared the deduced amino acid sequences for the peptides to known sequences. Sturgeon and whitefish have a PACAP(38) peptide sequence that is 92% conserved compared to human PACAP(38), the highest for a fish reported to date. GHRH is the lesser conserved of the two peptides with only 39% to 45% conservation between fish and human.Each of the five fish species had a second cDNA encoding a short precursor lacking GHRH(1-32), the bioactive portion of GHRH. This suggests that exon skipping in GHRH-PACAP transcripts may be an important mechanism for regulating the ratio of PACAP to GHRH peptides.
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Affiliation(s)
- Bruce A Adams
- Department of Biology, University of Victoria, BC, Canada
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Shahbazi F, Conlon JM, Holmgren S, Jensen J. Effects of cod bradykinin and its analogs on vascular and intestinal smooth muscle of the Atlantic cod, Gadus morhua. Peptides 2001; 22:1023-9. [PMID: 11445229 DOI: 10.1016/s0196-9781(01)00420-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The effects of [Arg(0),Trp(5),Leu(8)]-BK (cod [Arg(0)]BK) on vascular preparations from branches of the cod celiac artery and on longitudinal smooth muscle preparations from the cod intestine were investigated. Cod [Arg(0)]BK (3 x 10(-8) M) caused a relaxation of the celiac artery precontracted with adrenaline. The relaxation was abolished by the cyclooxygenase inhibitor indomethacin, suggesting that the effect is mediated through the release of prostaglandins, but there was no evidence for the involvement of leukotrienes or nitric oxide in the response. In the intestinal preparations, cod [Arg(0)]BK produced concentration-dependent contractions (pD(2) = 8.28 +/- 0.16). Experiments with N-terminally and C-terminally truncated analogs and with alanine-substituted analogs of cod [Arg(0)]BK demonstrate that the central amino acid Gly(4) and the C-terminal amino acids Leu(8) and Arg(9) are the most important in determining the conformation of the peptide that interacts with the receptor. The results indicate that the ligand binding properties of the cod BK receptor are considerably different from the receptor present in trout tissues and may resemble those of the mammalian B(2) receptor more closely.
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Affiliation(s)
- F Shahbazi
- Department of Zoophysiology, Göteborg University, Box 463, SE 405 30 Göteborg, Sweden
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Abstract
Gut motility in non-mammalian vertebrates as in mammals is controlled by the presence of food, by autonomic nerves and by hormones. Feeding and the presence of food initiates contractions of the stomach wall and subsequently gastric emptying, peristalsis, migrating motor complexes and other patterns of motility follow. This overview will give examples of similarities and differences in control systems between species. Gastric receptive relaxation occurs in fish and is an enteric reflex. Cholecystokinin reduces the rate of gastric emptying in fish as in mammals. Inhibitory control of peristalsis is exerted, e.g. by VIP, PACAP, NO in fish and amphibians, while excitatory stimuli arise from nerves releasing tachykinins, acetylcholine or serotonin (5-HT). In crocodiles, we have found the presence of the same nerve types, although the effects on peristalsis have not been studied. Recent studies on signal transduction in the gut smooth muscle of fish and amphibians suggest that external Ca2+ is of great importance, but not the only source of Ca2+ recruitment in tachykinin-, acetylcholine- or serotonin-induced contractions of rainbow trout and Xenopus gastrointestinal smooth muscle. The effect of acetylcholine involves reduction of cAMP-levels in the smooth muscle cells. It is concluded that, in general, the control systems in non-mammalian vertebrates are amazingly similar between species and animal groups and in comparison with mammals.
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Affiliation(s)
- C Olsson
- Department of Zoophysiology, University of Göteborg, Box 463, SE 405 30, Göteborg, Sweden
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