No abstract available.
Adrenalectomy ; Arginine Vasopressin/diagnostic use ; Catecholamines/physiology ; Cushing Syndrome/diagnosis/*physiopathology/surgery ; Humans ; Hydrocortisone/*secretion ; Male ; Middle Aged ; Vasopressins/physiology

The effects of paraventricular nucleus (PVN) stimulation and vasopressin on gastric ischemia-reperfusion injury (GI-RI) were investigated in male SD rats of which the celiac artery was clamped for 30 min and reperfused for 1 h by removal of the clamp. The results were as follows. Both electrical and chemical stimulation of the PVN obviously attenuated the GI-RI. Bilateral electrolytic lesion of the nucleus tractus solitarius (NTS) or microinjection of AVP-V(1) receptor antagonist into the NTS could eliminate the protective effect of electrical stimulation of the PVN on GI-RI. Hypophysectomy did not influence the effect of electrical stimulation of the PVN. Both vagotomy and sympathectomy could increase the effect of stimulating PVN on GI-RI. Microinjection of arginine-vasopressin (AVP) into the PVN also attenuated the effect on GI-RI. These results suggest that the PVN and AVP participate in the regulation of GI-RI and play an important role in protection against GI-RI. This protective effect of PVN on GI-RI might be mediated by activation of AVP-ergic neurons in the PVN, which release AVP from the descending projection fibers and activate the AVP-V(1) receptors on the NTS neurons. The vagus and sympathetic nerves are involved in the efferent pathway exerting their effects on GI-RI. Hypophysis does not seem to be involved in the protective effect of PVN stimulation.
Afferent Pathways ; physiology ; Animals ; Electric Stimulation ; Male ; Paraventricular Hypothalamic Nucleus ; drug effects ; physiology ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; physiopathology ; therapy ; Stimulation, Chemical ; Stomach ; blood supply ; Sympathetic Nervous System ; physiology ; Vagus Nerve ; physiology ; Vasopressins ; pharmacology

OBJECTIVEThis study investigates the plasma vasoactive substances and antioxidant enzymes levels in prehypertensive patients.

METHODSPatients were scruited according to JNC-7 and divided into three groups: 74 normotensive subjects (NT group, 38 males, mean age 47.15 +/- 7.77 years old); 51 prehypertensive patients (PH group, 29 males, mean age 47.82 +/- 5.16 years old) and 71 essential hypertensive patients (EH group, 37 males, mean age 48.25 +/- 7.97 years old). Serum lipids and plasma angiotensin II (Ang II), endothelin (ET), vasopressin (AVP), calcitonin gene-related peptide (CGRP), nitric oxide synthase (NOS), superoxide dismutase (SOD) and glutathione peroxidase (GPX) by radioimmunoassay and enzyme linked immunosorbent assay.

RESULTSSerum Lipids (TG, CHO and LDL) were significantly higher in the PH and EH groups compared to NT group (all P < 0.05). Ang II, AVP and ET were significantly increased while CGRP decreased in the EH group than that in NT group (all P < 0.05). SOD was significantly lower while GPX significantly higher. Further more, in the PH and EH groups than those in the NT group (all P < 0.05).

CONCLUSIONSOD was reduced and GPX increased in prehypertensive patients.

Adult ; Angiotensin II ; blood ; Antioxidants ; Blood Pressure ; physiology ; Calcitonin Gene-Related Peptide ; blood ; Case-Control Studies ; Endothelins ; blood ; Female ; Glutathione Peroxidase ; blood ; Humans ; Hypertension ; blood ; Male ; Middle Aged ; Nitric Oxide Synthase ; blood ; Plasma ; metabolism ; Superoxide Dismutase ; blood ; Vasopressins ; blood