[Effect of N-stearoylethanolamine(NSE) on activity of angiotensine-converting enzyme in the brain structures and blood plasma of rats with streptozotocine-induced diabetes].

The influence of saturated N-acylethanolamine--N-stearoylethanolamine (NSE) on the activity of angiotensine-converting enzyme (ACE) in the brain structures of rats with streptozotocine-induced diabetes was studied. It was shown that decreased activity of ACE was observed in the hypothalamus, increased--in the anterior pituitary. The NSE suspension administration to rats with experimental diabetes in a dose 50 mg/kg of body weight during 10 days caused a decrease in ACE activity in the anterior pituitary, whereas in the hypothalamus and hippocampus ACE activity did not change significantly. At the same time, introduction of NSE to intact animals led to the reduction of activity of ACE in the hippocampus, anterior pituitary and blood plasma. It is known that the highest amount of ACE in the brain structures is located in the membrane-bound state. Thus, the changes we have found in the activity of ACE in the control rats and in animals with induced diabetes may be related to the ability of NSE to the modulation of cell membranes lipid profile. Changes in the activity of ACE under the action of N-acylethanolamines may be one of the mechanisms for implementation of anti-hypertensive and anti-inflammatory action of these compounds.

[The activity of the enkephalinergic systems of the brain and hypophysis in experimental hypocorticism]. / Aktyvnist' enkefalinerhichnoï systemy mozku ta hipofiza za umov eksperymental'noho hipokortytsyzmu.

Changes in activity of basic components of enkephalinergic system, leu-enkephalin contents, activity of enkephalin-hydrolysing enzymes (enkephalinases A and B, enkephalin aminopeptidases) and 3H-leu-enkephalin specific binding to opioid receptor in rat anterior and mediobasal hypothalamus, striatum, medulla oblongata and adenohypophysis have been analysed on experimental models of hypocorticoidism. No changes in brain and pituitary body leu-enkephalin contents following unilateral hypocorticoidism. No changes in brain and pituitary body leu-enkephalin contents following unilateral adrenalectomy were shown. Bilateral adrenalectomy resulted in two-phase character of neuropeptide level: a decrease of leu-enkephalin contents in hypothalamus, striatum and adenohypophysis on the 7th day and its increase to the normal level on the 10th day after the operation were revealed. A decrease of leu-enkephalin contents in rat brain on the 7th day following adrenalectomy occurred simultaneously with a decrease in enkephalin aminopeptidase activity and specific binding of labeled leu-enkephalin testifying to strengthening of enkephalin release form neurosecretory granules of brain structures following adrenalectomy. Important changes in leu-enkephalin contents, reception and inactive processes on the level of adenohypophysis and on the level of hypothalamus, striatum and medulla oblongata were detected by cortisol and ACTH administration in adrenalectomised animals.

[Changes in the activity of the brain renin-angiotensin system and in the functional state of the pituitary-adrenal system of rats under the influence of captopril]. / Zminy aktyvnosti renin-anhiotenzynovoï systemy mozku ta funktsional'noho stanu hipofizarno-nadnyrkovoï systemy shchuriv pid vplyvom kaptoprylu.

While studying the effect of peroral captopril injections on the activity of renin-angiotensin system (RAS), the activity of angiotensin-converting enzyme (ACE) and angiotensin II content from anterior and mediobasal hypothalamus, medulla and adenohypophysis of intact rats has been established to decrease. Captopril administration decreases ACE activity which increases after hydrocortisone injection in rat medulla and striatum. Captopril results in no potentiation of hormonal effect in hypothalamus and in adenohypophysis where ACE activity decreases following hydrocortisone injection. A decrease in the RAS activity of brain structures and adenohypophysis induced by captopril administration to rats is accompanied by the inhibition of the activity in the pituitary-adrenal system. A decrease in ACTH level and in 11-hydroxycorticosteroids of the rat blood plasma has been determined after single captopril injection in the dosage of 10 and 50 mg/kg of body weight. Duration of the effect depends on the captopril dosage.