[The compensatory-adaptive reactions of the thyroid and adrenal adrenergic structures in the postnatal ontogeny of sympathectomized rats]

The study was performed in albino rats treated during first two postnatal weeks with guanetidin isotonic solution injected subcutaneously in dose 20 mg/kg body weight to obtain desympathization. Control animals received similar volume of the solution during equal terms. Thyroid and adrenal glands were studied in 1- and 6-month-old rats both by light and electron microscopes. Serotonin and catecholamines were revealed by fluorescent-histochemical method. In experimental 1-month-old animals morphological indexes indicate the thyroid gland hyperfunction. In these animals serotonin and catecholamines content is lower in parafollicular endocrinocytes, mast cells and in adrenergic fibres, the density of which is significantly lower than that in control animals. The adrenal gland weight in experimental animals increases due to the medulla. Serotonin and catecholamine content is essentially higher. Thyroid gland in 6-month-old experimental rats is hyperfunctioning. Adrenal fibres density in its stroma is close to control indexes. Catecholamines and serotonin adrenal glands medulla grows with age and remains higher than the appropriate control level, which indicates active participation of adrenal glands in adaptive reactions is desympathized animals. Serotonin plays an important role in local regulation of thyroid glands. Parafollicular endocrinocytes perform the function of local biogenic amines-producers, while mast cells regulate the serotonin content.

Decrease of pre-synaptic noradrenergic fiber density in rat hippocampus after transient ischemia

The selective loss of hippocampal CA-1 pyramidal neurons has been reported not to be accompanied by damage to presynaptic terminals in the stratum radiatum as shown by electron microscopic observations. However, we examined changes in the tyrosine hydroxylase (TH) immunoreactive fibers following transient ischemia in rats using an immunohistochemical method 1, 3, 7 and 30 days after ischemia. The present study indicates that ischemic neuronal injury spreads to pre-synaptic fibers after the disappearance of the post-synaptic CA-1 pyramidal neurons.

Molecular biology of adrenergic and dopamine receptors and the study of developmental nephrology

Neurotransmitters convey specific messages by binding to receptors on the cell membrane surface. Receptors are linked to membrane-bound, signal-transducing proteins which act as intermediaries in the generation of second messengers that elicit biological responses. Cell surface receptors could be grouped into families that utilize common systems for their signal transmission. These classes include the growth factor receptors, the transporter receptors which internalize their ligands, ion channels, and G-protein-coupled receptors. In the past few years, the cDNAs and/or genes of a number of G-protein-coupled receptors have been cloned. Structural analysis of the G-protein-coupled receptors, as well as the other classes of receptor, shows that those receptors which use a common signaling pathway have similar topographies and share significant sequence homology. Adrenergic and dopamine receptors are examples of receptors coupled to G proteins. This review outlines some strategies in the study of adrenergic and dopamine receptors using molecular biology techniques and how they relate to investigations in developmental nephrology.

[Molecular physiology of adrenoreceptors]

The paper reviews some problems of theoretical investigation of the spatial of adrenergic drugs and their receptors, citing results recently obtained by the authors. It includes the chapters as follows: Introduction; Conformation - activity relationships of ligands; Theoretical conformational analysis; Noradrenaline; Classification and some models of adrenergic receptors; Problems of ligands productive conformation selection and the description of receptor topography; Principles of choice of ligands; Criteria for productive conformation selection; Productive conformations of beta 2-adrenergic agonists and beta 2-receptor topography; Productive conformations of alpha 1-adrenergic receptor ligands and alpha 1-receptor topography; Structure-activity relationships of some ligands in the light of adrenergic beta 2- and alpha 1-receptors topography; Possible role of calcium ion in the interaction of adrenergic agonists with receptors.

The role of the autonomic nervous system in allergic diseases

The autonomic nervous system plays a significant role in the pathogenesis of allergic diseases, especially asthma. This paper details the components of the autonomic nervous system, defines the role that these individual components play in allergy and details the abnormalities found in the autonomic nervous system in allergic subjects that may contribute to the disease state.