The release of hydrolytic enzymes by the salivary glands and their content in the blood after unilateral nephrectomy

We studied the mechanisms of transformation of some salivary enzymes and established the real contribution of the salivary glands to the enzymatic homeostasis of the body in unilateral nephrectomy.The results were obtained that with unilateral nephrectomy, the content of amylase and pepsinogen in the blood increases, but its lipolytic activity remains unchanged, the volume of basal secretion of the salivary glands, the content and release of amylase by the parotid salivary gland increases. Unilateral nephrectomy stimulates the increment of pepsinogen by the gastric glands, and, accordingly, enhances its recreation from the blood, by the salivary glands. After unilateral nephrectomy, lipolytic activity and its secretion in saliva remain unchanged

Tear Replacement Therapy in Medical Support of Patients after Femto-LASIK Keratorefractive Surgery

Purpose — to analyze the effectiveness of artificial tear drops HYLOPARIN-COMOD® in the complex medical support of the FemtoLASIK operation based on monitoring of clinical, functional and morphometric indicators of the eye surface’s condition. Patients and methods. The study included 25 patients (50 eyes) who underwent a keratorefractive surgery (Femto-LASIK) and were prescribed instillations of artificial tear drops HILOPARIN-COMOD®. To analyze the effectiveness of artificial tear drops HYLOPARIN-COMOD® in the complex medical support of the Femto-LASIK operation based on monitoring of clinical, functional and morphometric indicators of the eye surface’s condition: UCVA, BCVA, Schirmer’s II test, tear break-up time (Norn’s test), OCT pachymetry of the cornea and corneal flap. The treatment effectiveness was evaluated at 1 day, 1 week, 1 and 3 months after the surgery. Results. As a result of the treatment, the following refractive data were obtained: UCVA increased from 0.09 ± 0.02 to 0.94 ± 0.07 on the first day after surgery and to 0.96 ± 0.04 and 0.99 ± 0.07 to 1 and 3 months of follow-up, BCVA respectively, from 0.97 ± 0.04 to 0.94 ± 0.07, 0.97 ± 0.07 and 0.99 ± 0.07 after surgery. A faster restoration of the cornea and corneal valve was revealed, as evidenced by a decrease in their thickness already in the 1st week after surgery in comparison with the control group, where were more pronounced changes occur only by the 1st and 3rd month of observation (p ≤ 0.05). There was a significant increase in the basal secretion of the lacrimal gland (Schirmer’s II test) from 10.16 ± 1.33 to 11.66 ± 1.13 and 12.88 ± 0.96 µm by 1 and 3 months after surgical treatment, respectively (p ≤ 0.05). The Norn’s test increased from 10.89 ± 1.94 to 12.78 ± 1.59 and 13.83 ± 0.5 s to 1 and 3 months of treatment, respectively (p ≤ 0.05). Conclusion. The effectiveness of the HILOPARIN-COMOD® use in the correction of the dry eye syndrome after keratorefractive operations has been proven. The obtained results clearly demonstrate that the HILOPARIN-COMOD® preparation enhances not only the stability of the tear film, but also the restoration of the OCT morphometric parameters of the thickness of the cornea and corneal flap.

A Single Membrane Protein Required for Atrial Secretory Granule Formation

The discovery of atrial secretory granules and the natriuretic peptides stored in them identified the atrium as an endocrine organ. Although neither atrial nor brain natriuretic peptide (ANP, BNP) is amidated, the major membrane protein in atrial granules is Peptidylglycine α-Amidating Monooxygenase (PAM), an enzyme essential for amidated peptide biosynthesis. Mice lacking cardiomyocyte PAM (PamMyh6-cKO/cKO) are viable, but a gene dosage-dependent drop in atrial ANP and BNP content occurred. Ultrastructural analysis of adult PamMyh6-cKO/cKO atria revealed a 20-fold drop in the volume fraction of secretory granules and a decrease in peripherally localized Golgi complexes. When primary cultures of Pam0-Cre-cKO/cKO atrial myocytes (PAM floxed, no Cre recombinase) were transduced with Cre-GFP lentivirus, PAM protein levels dropped, followed by a decline in proANP levels. Expression of exogenous PAM in PamMyh6-cKO/cKO atrial myocytes produced a dose-dependent increase in proANP content. Strikingly, rescue of proANP content did not require the monooxygenase activity of PAM. Unlike many prohormones, atrial proANP is stored intact and its basal secretion is stimulated by drugs that inhibit Golgi-localized Arf activators. Increased basal secretion of proANP was a major contributor to its reduced levels in PamMyh6-cKO/cKO myocytes; the inability of these drugs to inhibit basal proANP secretion by PamMyh6-cKO/cKO myocytes revealed a role for COPI-mediated recycling of PAM to the endoplasmic reticulum. Analysis of atrial coated vesicles and the ability PAM to make fluorescently-tagged proANP accumulate in the cis-Golgi region of cells lacking secretory granules revealed a non-catalytic role for PAM in soluble cargo trafficking early in the secretory pathway.SignificanceTransmission electron microscopy of atrial cardiomyocytes revealed dense granules resembling those in endocrine cells and neurons, leading to the discovery of the natriuretic peptides stored in these granules. Subsequent studies revealed features unique to atrial granules, including high level expression of Peptidylglycine α-Amidating Monooxygenase (PAM), an enzyme required for the synthesis of many neuropeptides, but not for the synthesis of natriuretic peptides. The discovery that atrial myocytes lacking PAM are unable to produce granules and that PAM lacking its monooxygenase activity can rescue granule formation provides new information about the proANP secretory pathway. A better understanding of the unique features of atrial cell biology should provide insight into atrial fibrillation, the most common cardiac arrhythmia, atrial amyloidosis and heart failure.

Neuroendocrine control of the pituitary gonadotropic function in experimental diabetes

The hypothalamo-pituitary-gonadal system was examined in male and female rats with experimental diabetes in­duced by streptozotocin (STZ). Injection of STZ caused a decrease of testosterone (T) concentration and of T nuclear receptors in the pituitary. The levels of luteinizing and follicle stimulating hor­mones (LH and FSH) in the blood of diabetic rats did not differ from those in intact animals. In vitro experiments showed that the development of diabetes did not change the basal secretion of LH by the pituitary in males. Maximal response to LH-RH was record­ed in control males after 3-hour incubation, whereas the rate of LH secretion in experimental rats did not differ from basal values. In­jection of STZ to cycling females disordered the estrous cycle and involved decreases of the basal and cyclic secretion of LH, FSH, and sex hormones. The concentrations of estradiol nuclear receptors in the preoptic anterohypothalamic region and pituitary decreased, whereas the number of T-binding sites decreased only in the pitui­tary. Sex hormone-stimulated gonadotropin wave in oophorect- omized females was decreased in diabetes, which was due to changed activity of the LH-RH producing system. The authors hy­pothesize that changes in the mechanism of regulation of the hy­pothalamo-pituitary-gonadal system in experimental diabetes are re­lated to pituitary disorders in males, whereas changed basal and cy­clic secretion of LH and FSH in females is caused by disordered activity of the LH-RH production and receptor binding at the level of the hypothalamo-pituitary complex.

Stimulation of Basal Secretion in the Treatment of Dry Eye Syndrome

The aim is to evaluate the effectiveness of Stillavit in the treatment of dry eye syndrome (DES) and its effect on the density of conjunctival goblet cells and the functional parameters of tear production. Methods. There were analyzed treatment results of 18 patients (36 eyes) with DES at the age of 48 to 80 years (average 60.6 ± 1.3 years) including 17 women and 1 male before and after 1 and 3 months after Stillavit prescription. In all patients in addition to a standard ophthalmological examination the results of Schirmer I, Norn, as well as the LIPCOF test were evaluated and the density of conjunctival goblet cells was examined. Results. After 1 and 3 months there was a significant improvement in the results of the Norn test: from 5.17 ± 0.22 seconds to 7.18 ± 0.17 seconds which indicated an increase in the stability of the tear film. After 3 months there was a significant increase in the density of conjunctival goblet cells, improvement in the Schirmer sample: from 9.26 ± 0.89 to 11.7 ± 0.6 mm (t = 2.28, p < 0.05) and LIPCOF test (t = 2.18, p < 0.05) which indicated an increase in tear production and a significant decrease in the inflammatory process and edema of the conjunctiva. Conclusion. Treatment of DES with the use of Stillavit leads after 3 months to a significant increase in the density of conjunctival goblet cells, increases tear production and stability of the tear film.

THE CHANGES OF HUMORAL ADRENERGIC REGULATION OF HEART IN ALCOHOL-TREATED RATS

Relevance. Under the chronic influence of ethanol the genes expression is changed which contain the information about synthesis of adrenergic receptors, epinephrine enzymes. However studies of the systemic manifestations of these changes are unknown. The distortion of the adrenergic drugs effect in an alcohol-treated organism is probable. Objective: to investigate the adrenergic regulation of the heart in alcohol-treated rates by means of variation of the number of β1 receptors and their ligands. Materials and methods. In control (n=10) and alcohol-treated rats chronically for 120 days (n=10) the number of β1-adrenergic receptors (by means of administration of concor cor selective blocker – 0,28 mg/kg) and the quantity of epinephrine in the blood (by means of activation of sympathoadrenal system after sodium caffeine-benzoate injection – 7,14 mg/kg) were varied. The concor cor and caffeine were administered separately and together. The heart rate (HR) was recorded with the help of sphygmomanometer. The results were processed by using MedStat package. Results. In alcohol-treated rats chronically the HR is 27,6±2,5% higher than in the control ones (383,8±12,9 min-1 and 300,8±8,7 min-1). The caffeine administration leads to an increase in heart rate by 11,5±1,1 % in control rats (up to 335,4±9,5 min-1) while it doesn’t affect this index in alcohol-treated rats (389,6±12,6 min-1). The blockade of β1 receptors leads to a decrease in the HR by 7,5±0,7 % (up to 278,2±7,9 min-1) in control rats and by 15,5±1,1 % (up to 324,4±9,3 min-1) in alcohol-treated rats. When co-administration the β1 receptors blocker and caffeine have nivelated the opposite effects of each other in the control rats and HR remained the same (307,0±8,2 min-1); this has resulted in a decrease in the HR by 4,8±1,0 % (up to 365,4±10,9 min-1) in alcohol-treated animals. Conclusions. It is assumed that the basal secretion of epinephrine is increased and the number of β1 receptors is decreased in alcohol-treated rats compared to control ones.

Peptide production and secretion in GLUTag, NCI-H716, and STC-1 cells: a comparison to native L-cells

GLUTag, NCI-H716, and STC-1 are cell lines that are widely used to study mechanisms underlying secretion of glucagon-like peptide-1 (GLP-1), but the extent to which they resemble native L-cells is unknown. We used validated immunoassays for 14 different hormones to analyze peptide content (lysis samples;n= 9 from different passage numbers) or peptide secretion in response to buffer (baseline), and after stimulation with 50 mM KCl or 10 mM glucose + 10 µM forskolin/3-isobutyl-1-methylxanthine (n= 6 also different passage numbers). All cell lines produced and processed proglucagon into GLP-1, GLP-2, glicentin, and oxyntomodulin in a pattern (prohormone convertase (PC)1/3 dependent) similar to that described for human gut. All three cell lines showed basal secretion of GLP-1 and GLP-2, which increased after stimulation. In contrast to freshly isolated murine L-cells, all cell lines also expressed PC2 and secreted large amounts of pancreatic glucagon. Neurotensin and somatostatin storage was low and secretion was not consistently increased by stimulation. STC-1 cells released more glucose-dependent insulinotropic polypeptide than GLP-1 at baseline (P< 0.01) and KCl elevated its secretion (P< 0.05). Peptide YY, which normally co-localizes with GLP-1 in distal L-cells, was not detected in any of the cell lines. GLUTag and STC-1 cells also expressed vasoactive intestinal peptide, but none expressed pancreatic polypeptide or insulin. GLUTag contained and secreted large amounts of CCK, while NCI-H716 did not store this peptide and STC-1 contained low amounts. Our results show that hormone production in cell line models of the L-cell has limited similarity to the natural L-cells.