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In chickens (84 birds) divided into 5 groups there was applied stress in the form of binding of legs and wings for 5 hours per day. Blood was taken by bleeding a group of 12 chickens after 1, 3, 7, 14, and 28 days. The level of adrenalin, noradrenalin and corticosterone were determined in the blood. The studies revealed a permanent significant decrease of the tested hormones up to 14 days of the experiment. At day 28 an increase of their levels was noted again. It was found a marked deviations in immunological indices as well.
Mammalian ovaries are chiefly innervated by the fibers of the adrenergic system although a cholinergic one also plays a certain role. In spite of lack any direct contact between adrenergic fibers, luteal cells and cells of the granulosa layer has been ascertained, denervation of the ovary results in malfunction of its secretory function. Noradrenaline affects the growth of ovarian vessicles as well as hastens the ovulation process. Moreover, catecholamines both in vitro and in vivo conditions stimulate the production of steroid hormones and oxytocin in ovary cells. This effect is caused by the direct action of catecholamines on membrane beta-adrenergic receptors in luteal cells as well as cells of the granular layer and theca externa. However, an indirect effect of catecholamines on ovarian hormone secretion through regulation of ovarian blood flow cannot be excluded. The amount of blood flowing through the corpus luteum is highest at the peak of its development and is dependent on the pressure in vessels carring blood to the ovary as apposed to the ovary stroma in which blood is under local autoregulation.
In this article the main factors stimulating biosynthesis and aldosterone secretion through the adrenal cortex cells have been discussed: i.e. the renin-angiotensin system, potassium, sodium and ACTH concentration in blood plasma. Aldosterone is a type of steroid hormone that acts primarily in renal collecting ducts to stimulate resorption of Na+ as well as secretion of K+ and H+. Its connections with intracellular receptors stimulate the manifestation of several genes in the nucleus. Transcription and subsequent translation result in the production of new proteins which modulate ionic transport systems located in the apical and basolateral membranes in the principal and intercalated cells of the collecting tubules. The early phase of aldosterone action corresponds with the activation of preexisting ionic channels and pumps, while the late phase corresponds with the synthesis of new channels proteins and new Na+-K+-ATPase units. The peculiar character of aldosterone activity in the neonatal period at people and chosen animal species has also been treated in this paper.
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