Two antiprothrombin antibodies against prothrombin and prothrombin-phosphatidyl serine show partial but not total identity

Recently, an enzyme-linked immunosorbent assay (ELISA) using prothrombin (PT) as the antigen has become a widely used test. Two ELISA methods for the detection of antiprothrombin antibody have been used extensively: one method employs PT as an antigen (aPT), and the other employs PT and phosphatidyl serine (aPT/PS) as antigens along with Ca. However, the results obtained by the two methods are not necessarily consistent with each other even using the same samples, suggesting the possibility that aPT and aPT/PS are different antibodies. We conducted an investigation to determine whether aPT and aPT/PS are identical or different antibodies. Five patients who were positive for both tests become negative to aPT after absorption with an aPT-ELISA plate or fluid-phase PT; however, they retained reactivity to aPT/PS after the same absorption procedure. These results suggest that aPT and aPT/PS are partially identical, yet still different antibodies. However, further examination employing more samples may be needed to verify our hypothesis including clarification of the clinicopathological significance of these antibodies in the future.

Overexpression of fatty acid synthase in oesophageal squamous cell dysplasia and carcinoma

OBJECTIVE

The expression of fatty acid synthase (FAS), an enzyme necessary for de novo fatty acid synthesis, has been examined in several types of tumours so far, but not in oesophageal cancer and dysplasia.

METHODS

We examined the immunohistochemical reactivity of FAS in 4 normal adult oesophagi, 14 dysplastic oesophageal lesions, and 80 squamous cell carcinomas and 6 cases with 4 special types of malignancies of the oesophagus. We also analysed the correlation between FAS expression and various clinicopathological features and long-term survival in patients with oesophageal cancer.

RESULTS

In the normal oesophagus, only faint cytoplasmic FAS expression was observed in cells of the basal layer. In contrast, FAS-positive cells were found in 92.9% of cases of dysplasia and 96.5% of cases of carcinoma including 6 cases with a specific histological subtype. However, high expression of FAS did not correlate with either clinicopathological features or prognosis of patients with oesophageal cancer.

CONCLUSION

Our results demonstrate that FAS is expressed in almost all oesophageal carcinomas of both usual and special types and dysplastic lesions, suggesting that FAS may be upregulated continuously from the early stage of oesophageal squamous cell carcinogenesis to established carcinoma.

Locally expressed CTLA4-Ig in a pancreatic beta-cell line suppresses accelerated graft rejection response induced by donor-specific transfusion

AIMS/HYPOTHESIS

This study examined whether locally expressed CTLA4-Ig can suppress the accelerated islet allograft rejection that is induced by donor-specific transfusion.

METHODS

CTLA4-Ig-transfected or parental MIN6 cells were transplanted subcutaneously into the right flank of streptozotocin-induced diabetic C3H/Hej mice with or without donor-specific transfusion. For donor-specific transfusion, spleen cells from C57BL/6 mice were injected i.v. at the time of transplantation. In other experiments, CTLA4-Ig-transfected and parental MIN6 cells were transplanted separately into each flank, together with donor-specific transfusion. Rejection was defined as a blood glucose concentration of more than 300 mg/dl in two consecutive measurements, and graft survival was confirmed by hyperglycaemia after the grafts were removed. The effect of an anti-CTLA4 antibody on the survival of CTLA4-Ig-transfected MIN6 cells was also examined.

RESULTS

In 7 of 12 donor-specific transfusion sensitised mice, CTLA4-Ig-transfected MIN6 cells remained viable 20 days after grafting, whereas all parental MIN6 cells ( n = 10) were rejected promptly, within 14 days. The prolonged allograft survival was observed even in the absence of detectable levels of serum CTLA4-Ig, while the surviving allografts continued to produce CTLA4-Ig in situ. This protection was abrogated by an anti-CTLA4 antibody, but not by a control antibody. Furthermore, six animals that maintained normoglycaemia after the separate transplantation of parental and CTLA4-Ig-transfected MIN6 cells into each flank all showed abrupt hyperglycaemia after the CTLA4-Ig/MIN6 graft was removed, suggesting that this protection operated locally.

CONCLUSION/INTERPRETATION

A beta-cell line genetically engineered to secrete CTLA4-Ig can protect a graft locally from the alloimmune response induced by donor-specific transfusion.

Odontogenic infection pathway to the submandibular space: imaging assessment

The aims of this study were to determine the pathways of odontogenic infection spread into the submandibular space and their relationship to the clinical symptoms. Computerized tomography (CT) and magnetic resonance (MR) images of 33 patients with submandibular involvement were analyzed. The spread of infection was evaluated by lateral asymmetry of the shape and density of the fascial spaces and tissues, and by obliteration of the interfascial fat spaces. Imaging findings were classified into three types: in 19 patients (57.6%), infection spread through the mylohyoid muscle or sublingual space (type I). In five patients (15.2%), infection spread through the bony structures of the mandible with periosteal reaction or perforation of the cortical plate (type II) and was associated with relatively mild symptoms. In four patients (12.1%), infection spread from the masticatory space (type III). Seven of 11 patients with dysphagia or fever showed submandibular involvement spreading into the parapharyngeal space. CT and MR imaging clearly demonstrated different pathways of the spread of odontogenic infection into the submandibular space, which influenced the manifestation of clinical symptoms.

Detection of genes expressed in primary colon cancers by in situ hybridisation: overexpression of RACK 1

AIMS

The isolation of various genes that are expressed in a region specific manner is considered useful for research in molecular pathology. In situ hybridisation (ISH) was used in a screening procedure to isolate these genes efficiently, using colon cancer as a model.

METHODS

Suppression subtractive hybridisation (SSH) between colon cancer tissue samples and corresponding non-cancerous tissues was performed. Genes showing high expression in the cancers were selected using macro-DNA array analysis. As a final screening procedure, conventional ISH was performed to isolate genes expressed specifically in colon cancers.

RESULTS

Sixty nine clones were selected by SSH and macro-DNA array analyses. These clones were then analysed by ISH to examine their expression patterns. ISH screening revealed that all the clones screened showed more intense signals in colon cancers than in non-cancerous tissues. Among them, RACK 1, which is a protein kinase C receptor and a homologue of the G protein beta subunit, was expressed intensely in colon cancer cells. RACK 1 expression was evaluated in multiple samples by ISH, and the results confirmed that RACK 1 was universally overexpressed in cells of all 11 colon cancers examined.

CONCLUSIONS

Many genes, including RACK 1, expressed in colon cancer cells can be isolated efficiently by this method, and their precise expression pattern can be evaluated. These results indicate that ISH is an excellent technique for systemic screening of genes expressed in a region specific manner.

Effects of preconditioning on ischemia/reperfusion injury of hepatocytes determined by immediate early gene transcription

Ischemia reperfusion (I-R) of the liver induces various events leading to cell death (apoptosis) and subsequent cells proliferation. Recent experimental studies have described the protective effect of ischemic preconditioning (IPC) on I-R injury of the liver. However, the mechanisms involved in this protection remain unknown. The protein products of immediate early genes (IEGs) behave as crucial transcriptional regulators not only in apoptosis but also in cell proliferation. Here, we evaluated the effects of IPC on IEG transcription after I-R injury, using a rat liver I-R injury model. Injury to hepatocytes was evaluated by measuring serum levels of aspartate transaminase (AST), alanine transaminase (ALT), and lactate dehydrogenase (LDH) and that to endothelial cells by plasma concentration of hyaluronic acid (HA). The extent of necrosis was evaluated by H&E staining, while cell proliferation and apoptosis were evaluated by proliferating cell nuclear antigen (PCNA) and terminal deoxy(d)-UTP nick end labelling (TUNEL) staining, respectively. Alterations in the transcription of IEGs (c-fos and c-jun) were examined by Northern blotting. Rats subjected to 40-min liver ischemia, preceded by 10-min preconditioning, showed significantly lower AST, ALT, LDH, and HA levels at 6 h after I-R than untreated animals (P < 0.05; n at least 5 rats per group). The percentage of necrotic areas at 24 h after I-R was significantly lower in IPC-treated animals than in the controls. The numbers of apoptotic cells at 24 h after I-R and the numbers of PCNA-positive cells at 24 and 48 h after I-R were significantly lower in IPC-treated rats than in controls. Transcription levels of IEGs were low in IPC-treated rats, particularly c-jun at 1 and 1.5 h after I-R (P < 0.05). Our results indicate that IPC provides a significant protective effect on for liver cells against I-R injury and that its effect is evidenced by a significant decrease in the transcription levels of IEGs following the insult.

Octreotide-induced suppression of the hyperglycemic response to neostigmine or bombesin: relationship to hypothalamic noradrenergic drive

Neostigmine (cholinesterase inhibitor) or bombesin, when injected into the third cerebral ventricle of awake rat, dose-dependently increased serum glucose with the simultaneous rise in hypothalamic noradrenergic neuronal activity (NAA). Co-administration of octreotide with neostigmine or bombesin suppressed the hypothalamic NNA response with the simultaneous inhibition of the hyperglycemic response. There was a close relationship between hypothalamic NNA and serum glucose in these studies. On the basis of the concept that hypothalamic noradrenergic drive plays an important role in mediating the hyperglycemic response to stressful stimuli, the present findings suggest that the hyperglycemic response to neostigmine or bombesin is mediated via the interaction with hypothalamic noradrenergic neurons.

[Implication on thyroid function tests]

We tried to investigate the present problems, concerning the reference individual and interval in thyroid function tests and find the solutions for them. We are now using healthy adults for the reference individual and interval. Recently, we found the sex-difference and age-related changes for reference individual and interval in free T3 measurement. We raised the questions on whether there are any sex-differences and/or age-related changes or not. Surprisingly, there were almost no detailed data about them especially in Japan. Therefore, we examined the Europe data, and found out some kind of sex-differences and age-related changes. We propose the following examinations using many Japanese population in order to provide a precise and proper reference individual and interval: 1. Whether there are any sex-difference in thyroid function tests? 2. Whether there are age-related change in thyroid function tests, for instance, simply dividing population into the immature, adult and the aged?

Induction of immediate early genes after partial hepatectomy in cholestatic liver

The protein products of immediate early genes (IEGs) behave as transcriptional regulators and play an important role in the regulation of gene expression associated with liver cell proliferation and apoptosis. The aim of this study was to examine whether the transcription of IEGs was induced by obstructive jaundice during liver regeneration after 70% partial hepatectomy, and to examine their association with animal survival, cell proliferation, and apoptosis. Obstructive jaundice (OJ) was induced in rats by common bile duct ligation (CBDL), and 70% partial hepatectomy was performed 5 days after CBDL (OJ group). Changes in the induction of the IEGs, c-fos and c-jun, were compared between control and OJ groups in relation to survival before and after partial hepatectomy. Cell proliferation and apoptosis were evaluated by proliferating cell nuclear antigen (PCNA) immunohistological staining and by an in situ TdT-mediated d-UTP-digoxigerin nick-end labeling (TUNEL) method. The 2-week survival in the OJ group (2/7) was significantly less that of the sham operation (control) group (7/7). Enhanced induction of IEGs was evident in the OJ group after partial hepatectomy compared with findings in the control group. The PCNA-labeling index (LI) in the OJ group was increased after partial hepatectomy, but only minimally, compared with that in control animals. Apoptotic cells appeared in bile ducts and surrounding hepatocytes after partial hepatectomy in the OJ group, although apoptotic cells were rare in the control group. IEG transcription does occur after partial hepatectomy in jaundiced liver but it is enhanced and sustained, and leads to apoptosis rather than leading to the efficient proliferation of hepatocytes.

Ulnar deviation after volar subluxation of the proximal interphalangeal joint

A rare case of irreducible and progressive ulnar deviation after volar subluxation of the proximal interphalangeal joint is presented. An immobilized proximal interphalangeal joint with remaining volar subluxation after improper reduction showed ulnar deviation at 3 weeks after injury. During surgery, the radial collateral ligament was found to be ruptured at its origin, with formation of concomitant scar tissues. There were no apparent lesions at the central slip, lateral band, and volar plate. Interposition of the ruptured ligament and infiltration of the surrounding scar tissues into the proximal interphalangeal joint were identified. Surgical incision of the capsule along the dorsal margin of the radial collateral ligament readily produced successful reduction. The irreducible and progressive ulnar deviation of the proximal interphalangeal joint seemed to result from gradual infiltration of the scar tissues, subsequent to remaining volar subluxation because of interposition of the ruptured collateral ligament.

Healing of full-thickness tears of avian supracoracoid tendons: in situ hybridization of alpha1(I) and alpha1(III) procollagen mRNA

Although clinically significant, much remains unknown about the healing of the torn rotator cuff tendon, because of unavailability of appropriate animal model. The human supraspinatus tendon faces the subacromial bursa superiorly, and the joint capsule inferiorly, while the digital flexor tendon is surrounded by the synovium. We hypothesized that the supraspinatus tendon heals by the process which is different from that observed with digital flexor tendons, in which epitenon cells migrate into the torn portion circumferentially. The avian supracoracoid tendon was adopted for this experiment because of its similarity to the human supraspinatus tendon. We developed a full-thickness tendon laceration followed by primary suture. The objective of this study was to detect localization of the responsible cells for repair of the tendon. We examined the process using histology and in situ hybridization. Starting at week 1 the peritendon cells of the bursal side proliferated and migrated into the laceration site. At week 6, the tendon stumps were continuous with new connective tissue. High-level expression of procollagen mRNA in the proliferating peritendon cells on the bursal side demonstrates to contribute to the reparative process, which progressed to the joint side. This mode of repair is different from that of the digital flexor tendon.

Interleukin-1-induced subacromial synovitis and shoulder pain in rotator cuff diseases

OBJECTIVE

To determine the relationship between the expression of interleukin-1beta (IL-1beta) and IL-1 receptor antagonists (IL-1ra) in the subacromial bursa and shoulder pain in rotator cuff diseases.

METHODS

Synovial specimens were analysed using various methods including reverse transcriptase-polymerase chain reaction (RT-PCR), immunohistochemistry and in situ RT-PCR. Thirty-nine patients with rotator cuff diseases were candidates. The degree of their shoulder pain was evaluated using a visual analogue scale.

RESULTS

The mRNA expression levels of the cytokines were significantly correlated with the degree of pain [IL-1beta: r=0.782; secreted IL-1ra (sIL-1ra): r=0.756; intracellular IL-1ra (icIL-1ra): r=0.806, P<0.001, respectively]. The combined results of immunohistochemistry and in situ RT-PCR analysis indicated that both synovial lining and sublining cells produce IL-1beta, while synovial lining cells predominantly produce icIL-1ra and sublining cells secrete sIL-1ra.

CONCLUSIONS

The differential regulation of the two forms of IL-1ra mRNAs may play an important role in shoulder pain in rotator cuff diseases, regulating IL-1-induced subacromial synovitis.

[A case of retroperitoneal malignant fibrous histiocytoma with marked response to cisplatin, ifosfamide and doxorubicin]

A 61-year-old man was admitted to our hospital in December 1994 for a suspected retroperitoneal tumor. Systemic imaging investigations demonstrated retroperitoneal solid tumor, which was diagnosed as malignant fibrous histiocytoma (MFH) by immunohistochemistry for alpha 1-antitrypsin. In March 1995, he was treated with 3 courses of systemic chemotherapy with cisplatin, ifosfamide and doxorubicin followed by the same therapy in March 1996, without serious side effects. MFH is known to be resistant to ordinary chemotherapy. However, the CT showed a marked decrease in the size of the tumor, and the tumor disappeared within 2 months after the first treatment. The patient also recovered rapidly from abdominal pain, for which complete remission has been achieved for more than 5 years. The present chemotherapy may be an effective treatment for retroperitoneal MFH.

THE LONG-TERM OUTCOME OF LAPAROSCOPIC RADICAL NEPHRECTOMY FOR SMALL RENAL CELL CARCINOMA

PURPOSE

To evaluate the efficacy of laparoscopic radical nephrectomy in patients with small renal cell carcinoma, we analyzed the long-term results in those treated with laparoscopy and those undergoing open surgery.

MATERIALS AND METHODS

A total of 149 patients with tumors less than 5 cm. in diameter enrolled in a radical nephrectomy program between January 1992 and March 2000. Of these patients 103 were treated laparoscopically and the remaining 46 underwent open surgery. Patient followup was until June 30, 2000.

RESULTS

Laparoscopy followup was from 3 to 95 months (median 29). A total of 100 patients survived, 2 died without any recurrent disease in months 34 and 45, respectively, and 1 dropped out in postoperative month 3. Seeding of the port sites did not develop in any of the patients. There were 3 patients who had metastatic disease in months 3, 19 and 61, respectively, and 1 had local recurrence in postoperative month 43. The 5-year disease-free and patient survival rates were 95.1%, and 95.0%, respectively. Except for 2 patients who dropped out in months 10 and 16, respectively, 44 who underwent open surgery were followed from 11 to 101 months (median). Of the 44 patients 41 survived without any recurrent disease, 1 also survived with metastasis and 2 died of metastatic disease in months 7 and 11, respectively. The 5-year disease-free and patient survival rates were 89.7% and 95.6%, respectively.

CONCLUSIONS

Laparoscopic radical nephrectomy can be an alternative to open nephrectomy in patients with localized small renal cell carcinoma.

[Peripheral blood stem cell harvest for patients with germ cell tumors]

From January 1996 to December 1999, fifteen patients with germ cell tumors underwent peripheral blood stem cell harvest during 15 courses of bleomycin, etoposide, cisplatin (BEP), 4 courses of etoposide, ifosfamide, cisplatin (VIP) and 3 courses of high-dose etoposide mobilization at Nagoya University Hospital. We performed 29 aphereses during BEP, eight during VIP, and six during high-dose etoposide. Although we were able to harvest 4.4 x 10(6)/kg of median CD34 positive cells per apheresis during BEP, the number of stem cells (more than 4 x 10(6)/kg of CD34 positive cells), which are needed for tandem high-dose chemotherapy, could not be obtained during four courses of BEP. For three patients in whom white blood cell counts at nadir were 2,000/microL or more, however, the required number of CD34 positive cells were harvested. VIP provided only 1.7 x 10(6)/kg of median CD34 positive cells per apheresis, while, 7.3 x 10(6)/kg of CD34 positive cells were harvested during high-dose etoposide mobilization. The dose of G-CSF was a significant factor for the number of CD34 positive cells harvested during BEP (p = 0.02); however, there might be some relationship between the harvest and the number of the peripheral white blood cells on the day of apheresis (p = 0.08), the day to start G-CSF (p = 0.13), or the day to initiate apheresis (p = 0.27). Based on our experience, it is recommended that 5 micrograms/kg of G-CSF should be started from the 14th or 15th day of BEP until the last apheresis and that aphereses should be performed between the 19th and 21st day, especially at the days when the peripheral white blood cell count increases beyond 10,000/microL.

[Experience of specific immunotherapy with standardized Japanese cedar pollen extract]

A study was conducted in 165 subjects with Japanese cedar pollinosis (JC) to evaluate the switching to the new standardized extract (SE) for patients who are going on specific immunotherapy (SP-IT) with conventional non-standardized extracts, products of Trii Co. or Hollister-Stier Co. Eight of 137 subjects exhibited adverse systemic reactions such as general skin eruption and despnea when JC allergen extract of Hollister-Stier Co. was switched to JC-SE. There were 6 cases where concentration of the extract had to be decreased due to extraordinary late reactions, while none of 28 subjects exhibited adverse side effect, when conventional allergen extract by Torii Pharmaceutical Co. was switched to JC-SE. Careful switching to high concentration of SE is required, because eight cases with adverse side effect were shown in switching to 200 JAU/ml and 2000 JAU/ml. 20 subjects started with SP-IT by JC-SE after spread of JC in the year of 2000 exhibited no adverse side effects in our protocol.

Vascular endothelial growth factor (VEGF) expression in the subacromial bursa is increased in patients with impingement syndrome

Vascular endothelial growth factor (VEGF), which is known to be an angiogenetic factor, plays an important role in the inflammation of synovial tissue. To investigate the relationships between VEGF and clinical symptoms in rotator cuff disease, VEGF expression was examined using RT-PCR and immunohistochemical analysis in 50 patients with this disease (26 with full-thickness cuff tear, 12 with partial-thickness tear, and 12 with subacromial bursitis). VEGF mRNA expression was detected in 40 out of 50 patients by RT-PCR. VEGF mRNA expression was found more frequently in the patients with motion pain (39 out of 41) than in those without motion pain (1 out of 9) with statistical significance (Fisher's test, P < 0.001). Thirty-one out of 33 patients with synovial proliferation showed VEGF mRNA expression, whereas the expression of this transcript was found in 9 out of 17 patients without synovial proliferation. This association with synovial proliferation was also significant (Fisher's test, P = 0.0013). Thirty out of 41 patients with motion pain had synovial proliferation but 3 out of 9 patients without motion pain had synovial proliferation. In all these 30 patients with both motion pain and synovial proliferation, VEGF mRNA expression was detected. This association between motion pain and synovial proliferation was also significant (Fisher's test, P < 0.05). The mean vessel count and area in subacromial bursa expressing VEGF was significantly higher than in those without VEGF (Mann Whitney's U test, P < 0.01). These results suggested that VEGF expression is associated with vascularity, synovial proliferation and shoulder motion pain in the rotator cuff disease.

New approaches for successful islet transplantation

The long-term control of glucose metabolism is expected to be achieved with insulin-secreting pancreatic islets transplanted as the whole pancreas or isolated islet tissue. The current clinical outcomes of such procedures are unsatisfactory compared with that of whole organ transplantation or experimental islet transplantation, although the safety of the transplantation procedure itself is assured. In this review, we first describe the immunological characteristics of purified islets in an attempt to explain the differences between the results for human and experimental islet transplantation. We then introduce new approaches currently undertaken in our laboratory that could, we hope, make islet transplantation more successful.

Blood flow in and around the masseter muscle: normal and pathologic features demonstrated by color Doppler sonography

OBJECTIVE

The purpose of this study was to clarify the normal findings of arteries in and around the masseter muscle and to present their pathologic changes with the use of color Doppler sonography.

STUDY DESIGN

The vascular appearances were examined for the 4 main arteries feeding the masseter muscle in healthy volunteers (n = 38) and patients with inflammation (n = 5) and intramuscular hemangioma (n = 3). The features of these arteries were investigated together with the flow diameter, flow velocities, and arterial resistances. The symmetry indices were also calculated to assess the pathologic changes.

RESULTS

The detection rates of the branch from the transverse facial artery, the masseter artery, and the branch from the maxillary or external carotid artery were 98.7%, 21.1%, and 84.2% in healthy volunteers, respectively. The facial artery that feeds the muscle from the inferior part represented 2 patterns according to anatomic variant: the masseteric branch (22.4%) and the main trunk itself (77.6%). The means of the flow diameter, maximum and minimum velocities, resistive index, and pulsatility index in healthy subjects were 1.8 mm, 24.6 cm/s, 5.1 cm/s, 0.80, and 2.51, respectively. In most of the patients with symptoms, the symmetry indices of all measurement values increased in comparison with those of healthy volunteers.

CONCLUSION

Color Doppler sonography is useful in describing the arteries in and around the masseter muscle and has the potential of being used to depict the pathologic changes.

Central suppressive effect of octreotide on the hyperglycemic response to 2-deoxy-D-glucose injection or cold-swim stress in awake rats: possible mediation role of hypothalamic noradrenergic drive

Somatostatin (SRIH) and its analog have been reported to act within the central nervous system to suppress the hyperglycemic response to a variety of neural stimuli. On the other hand, the hyperglycemic response to 2-deoxy-D-glucose (2-DG) injection or cold-swim stress is well demonstrated to be closely associated with an increase in hypothalamic noradrenergic neuronal activity (NNA). To evaluate whether the suppression of the hypothalamic NNA response could be involved in the central mechanism whereby a SRIH analog inhibits the hyperglycemic response, octreotide, a clinically used long-acting octapeptide SRIH analog, was administered into the third cerebral ventricle of awake rats prior to the intraperitoneal injection of 2-DG or cold-swim stress. Hypothalamic noradrenaline (NA) and its neuronal metabolite, 3,4-dihydroxyphenylethyleneglycol (DHPG), were analyzed, and the ratio of DHPG to NA was used as an index of NNA. Intracerebroventricular (i.c.v.) pretreatment with octreotide suppressed the 2-DG-induced increase in hypothalamic NNA, accompanied by the inhibition of the serum glucose, NA and adrenaline responses. This suppressive effect of octreotide was dose-dependent. Similarly, i.c.v. pretreatment with octreotide prevented the hypothalamic NNA response to cold-swim stress, accompanied by a blockade of the increases in serum glucose, NA and adrenaline. A close relationship between hypothalamic NNA and serum glucose emerged from these studies. Intraperitoneal pretreatment with octreotide had no significant effect on the hyperglycemic or hypothalamic NNA response to 2-DG injection. These findings suggest that the inhibitory effect of octreotide on the hypothalamic NNA response to 2-DG injection or cold-swim stress is associated with the simultaneous suppression of the hyperglycemic response. Supporting the concept that hypothalamic NNA contributes to the modulation of blood glucose in stressful conditions, it is suggested that the suppression of the hypothalamic NNA response is, at least in part, involved in the central mechanism by which octreotide inhibits the hyperglycemic response to 2-DG injection or cold-swim stress.