The structure of spleen in the long-legged buzzard (Buteo rufinus): Histological and immunohistochemical study.

The aim of this study was to examine the structure of the spleen in the long-legged buzzard (Buteo rufinus) by histologically and the distribution of the catalase in the spleen by immunohistochemically. The tissue materials were taken from three healthy long-legged buzzards provided by permission of the General Directorate of Nature Protection and National Parks (Ankara, Turkey). The long-legged buzzard spleen is surrounded by smooth muscle cells and fibrous connective tissue. In addition, trabecular structures are not found in the capsule. The separation of white and red pulp areas could not be precisely determined. Plasma cells were detected especially around the lymphoid follicles and lymphatic follicles and Schweigger-Seidel cells were formed by reticulum strands. Alcian blue positive reaction was determined in Schweigger-Seidel cells and endothelial cells of the long-legged buzzard spleen. The intense cytoplasmic catalase immunoreactivity was observed in the Schweigger-Seidel cells and nuclear in some red pulp cells of the long-legged buzzard spleen. Consequently, determination of the histological structure and catalase immunoreactivity of the spleen on the long-legged buzzard by this study could be support for the future researches.

Pleiotropic vascular effects of ivabradine in streptozotocin-induced diabetes.

AIMS: Ivabradine (IVA) reduces heart rate (HR) by inhibiting hyperpolarization-activated cyclic nucleotide-gated (HCN) channels in sinoatrial node. Studies suggest that IVA has other beneficial effects on cardiovascular system that are not related to its effect on HR such as prevention of endothelial injury and the antioxidant effects. In addition to sinoatrial node, HCN channels exist in other tissues and their expression pattern differs in certain pathologies such as hypertension and hypertrophy. We investigated the mechanism of IVA effect in the setting of streptozotocin (STZ)-induced cardiovascular damage. Direct effects of IVA and their mechanism on thoracic aorta as well as possible prevention of vascular dysfunction in diabetes were investigated in this study. METHODS AND RESULTS: The effects of IVA on vascular function were investigated in control and STZ-diabetic rats. Some control and diabetic rats were treated with IVA. IVA treatment prevented diabetes-induced increase in plasma p-selectin and vascular cell adhesion molecule-1 levels and the decrease in nitric oxide content in the aortas of diabetic animals. When added to isolated organ bath, IVA induced concentration-dependent relaxations in thoracic aorta. Pre-incubation with Nω-Nitro- L -arginine methyl ester reduced IVA-induced relaxations. Expression patterns of all isoforms of HCN proteins were affected by both diabetes and IVA treatment. CONCLUSION: IVA improves vascular function in diabetes and HCN channels support vascular activity against damaging effects of diabetes. IVA may be added to prevent diabetic cardiovascular dysfunction with these beneficial effects that are unrelated to its primary mechanism of action.

Expression pattern of galectin-1 and galectin-3 in rat testes and epididymis during postnatal development.

Galectins are a family of lectins-binding beta-galactosides involved in a variety of extracellular and intracellular processes, thereby contributing to homeostasis, cell adhesion, cellular turnover, and immunity. This study aimed to determine the localization and expression of galectin-1 (Gal-1) and galectin-3 (Gal-3) in the testis and epididymis of rats at postnatal [(prepubertal (day 5), pubertal (day 20), postpubertal (day 50) and mature (day 70)] periods by using immunohistochemistry and Western blotting. Gal-1 and Gal-3 were differentially expressed in different types of cells in the testis and epididymis during postnatal development. While we detected Gal-1 expression in some spermatogenic cells and Leydig cells in the testis, not in the epididymal epithelium, Gal-3 was expressed in Sertoli cells, peritubular myoid cells, Leydig cells, smooth muscles and interstitial CD68-positive macrophages. Epithelial cells of the corpus and cauda epididymis showed an intense Gal-3 expression. Gal-1 expression was higher in the testis than in the epididymis on days 50 and 70. The expression of Gal-3 in the testis increased from the prepubertal to mature period. While the expression difference of Gal-3 was not statistically significant in the testis and epididymis until puberty, Gal-3 expression in the postpubertal and mature periods was higher in the epididymis. The expression of Gal-3 in the corpus and cauda epididymis was higher than that in the caput epididymis. In conclusion, our findings suggest that puberty has potential regulatory effect on the expression of galectins in testis and epididymis of rats. Gal-1 and 3 may play a role in the development of the reproductive system and the preservation of the immune-privileged environment in the testis, due to their pro-apoptotic and anti-apoptotic functions. The presence of intense expression of Gal-3 in the corpus and cauda epididymis may contribute to the maturation and storage of spermatozoa.

Histologic structure of the uropygial gland of the osprey (Pandion haliaetus).

This study was performed to determine the histologic structure of the uropygial gland in an osprey. The gland was composed of two elongated lobes which were enclosed in a capsule of connective tissue. Each lobe of the gland had a large central cavity with one excretory duct. The secretory tubules consisted of four cell types: basal, intermediate, secretory, and degenerative. The intermediate cells in the osprey were few in number and did not form a layer, while secretory and degenerative cells consist of 2-3 strata, indicating a high level of lipogenesis. The membranes and peripheral cytoplasm of degenerative cells located in the base of the lobes revealed calcium (Ca2+) deposition and an intense acidophilic reaction.

Biomechanical and histological outcome of combined raloxifene-estrogen therapy on skeletal and reproductive tissues.

Estrogen replacement is a potent therapy for postmenopausal osteoporosis. However, its carcinogenic effects on breasts and the uterus limit its utilization. Raloxifene has estrogen-like effects on bones without the carcinogenic symptoms on breast or uterine tissue. Their individual effects are well characterized, but the results of their interaction remains elusive. In this work, we investigate the consequences of a combined raloxifene/estrogen therapy on bone and uterus with experimental osteoporosis. 40 Wistar rats began treatment 3 months post-ovariectomy. Estrogen and raloxifene were administered 0.03 mg/kg/day and 1.5mg/kg/day separately and together for 5 times per week for 12 weeks. Biomechanical tests and bone mineral density measurements, histology of uterus, and blood markers were analyzed. The co-administration group had higher toughness and ultimate strength than the ovariectomized controls (P<0.01). E+R had better biomechanical properties than the single treatments; yet the differences were not significant. Uterus histology signified high degeneration in the estrogen group. The raloxifene group had less degeneration but higher vascularization. Less immune reaction and vascularization were observed in the group with combined dosage than in those with individual treatments. Hence, the uterus of the combined treatment had fewer side effects than the ones that were individually treated. Mutual antagonization might be possible between raloxifene and estrogen, and that might have caused a decrease in the adverse effects. Overall, combined therapy might be useful to minimize the individual side effects of raloxifene and estrogen on the uterus and still provide bone strength and toughness.

Nasal administration of metoclopramide from different dosage forms: in vitro, ex vivo, and in vivo evaluation.

Nasal drug delivery is an interesting route of administration for metoclopramide hydrochloride (MTC) in preventing different kind of emesis. Currently, the routes of administration of antiemetics are oral or intravenous, although patient compliance is often impaired by the difficulties associated with acute emesis or invasiveness of parenteral administration. In this perspective, nasal dosage forms (solution, gel, and lyophilized powder) of MTC were prepared by using a mucoadhesive polymer sodium carboxymethylcellulose (NaCMC). In vitro and ex vivo drug release studies were performed in a modified horizontal diffusion chamber with cellulose membrane and excised cattle nasal mucosa as diffusion barriers. The tolerance of nasal mucosa to the formulation and its components were investigated using light microscopy. In vivo studies were carried out for the optimized formulations in sheep and the pharmacokinetics parameters were compared with oral solution and IV dosage form. The release of MTC from solution and powder formulations was found to be higher than gel formulation (p < 0.05). Histopathological examination did not detect any severe damage. Hydroxypropyl-beta-cyclodextrin (HPbetaCD) used in powder formulations was found to be effective for enhancing the release and absorption of MTC. In contrast to in vitro and ex vivo experiments nasal bioavailability of gel is higher than those of solution and powder (p < 0.05). In conclusion, the NaCMC gel formulation of MTC with mucoadhesive properties with increased permeation rate is promising for prolonging nasal residence time and thereby nasal absorption.

Nasal absorption of metoclopramide from different Carbopol 981 based formulations: In vitro, ex vivo and in vivo evaluation.

There is a need for nasal drug delivery of metoclopramide HCI (MTC) in specific patient populations where the use of commercially available intravenous and oral dosage forms may be inconvenient and/or unfeasible. In this perspective, nasal dosage forms (solution, gel and lyophilized powder) of MTC were prepared by using a mucoadhesive polymer Carbopol 981 (CRB 981). The drug release studies of formulations were performed by using a modified horizontal diffusion chamber with cellulose membrane and excised cattle nasal mucosa as diffusion barriers. After the ex vivo experiments, the morphological appearances of the nasal mucosa were analyzed with the light microscopic studies. In vivo experiments were carried on sheep model. The release of MTC from solution and powder formulations was found higher than gel formulation (p < 0.05) and no severe damage was found on the integrity of nasal mucosa after ex vivo experiments. The penetration enhancing effect of dimethyl-beta-cyclodextrin (DM-beta-CD) used in powder formulations was observed in ex vivo and in vivo experiments. In contrast to in vitro and ex vivo experiments the nasal bioavailability of gel formulation was found higher than those of the solution and powder (p < 0.05) and might represent a promising novel tool for the systemic delivery of MTC.