Search results for "wistar"
showing 10 items of 1094 documents
Determination of renal tissue ibandronate levels in rats with normal and mildly impaired renal function
2013
After entering the blood, bisphosphonates are immediately bound to bone or excreted unchanged by the kidney. During renal excretion about 0.5% of administrated dosage remains in kidney tissue. The renal tissue level of bisphosphonates (RTL) decreases over time and remains at about 0.15% after 3weeks, but the influence of renal insufficiency (RI) is unclear.We investigated the influence of mild to moderate RI on RTL of ibandronate (IBD). First a method for determination of RTL was implemented and validated. We measured RTL in rats with normal renal function (SHAM) and after unilateral nephrectomy (UNX). In each case one SHAM and one UNX groups received one or alternatively 9 times every 3wee…
Potential role of the neuropeptide CGRP in the induction of differentiation of rat hepatic portal vein wall.
2005
The media of the rat hepatic portal vein is composed of an internal circular muscular layer (CL) and an external longitudinal muscular layer (LL). These two perpendicular layers differentiate progressively from mesenchymal cells within the first month after birth. In this paper, we studied the development of calcitonin gene-related peptide (CGRP) innervation during post-natal differentiation of the vessel. We show that CGRP innervation is already present around the vessel at birth in the future adventitia but far from the lumen of the vessel. Progressively, CGRP immunoreactive fibers reached first LL then CL. CL by itself become only innervated at day 14 after birth. This corresponds to the…
The hypothalamic magnocellular neurosecretory system in developing rats
2009
Studies concerning the development of the magnocellular system are scarce and discordant in literature. We carried out an immunohistochemical study on supraotic and paraventricular hypothalamic nuclei using antivasopressin and antioxytocin antibodies in developing rats between the 15th day of intrauterine life and the 6th day of postnatal life. In addition, we performed RT-PCR experiments to establish the stage at which these hormones appear and neurosecretory activity commences. The results showed that supraoptic and paraventricular nuclei appear, respectively, on the 16th and the 18th day of intrauterine life and both immediately synthetize vasopressin neurohormone. By contrast, synthesis…
Transferrin gene expression in the mammary gland of the rat. The enhancing effect of 17 beta-oestradiol on the level of RNA is tissue-specific.
1993
We have investigated the physiological factors which regulate transferrin gene expression in the mammary gland of the rat. Our studies by dot blot analysis have demonstrated that multiple doses of 17β-oestradiol (OE2; 0·5 mg/kg per day for 3 days) elicit a specific 3·5-fold increase in the transferrin mRNA levels in the mammary glands of virgin rats. The hormonal action of OE2 in mammary tissue was specific for the transferrin gene, as judged by hybridization with β-actin cDNA. The accmulation of transferrin mRNA induced by OE2 treatment was similar to the developmentally regulated expression of the gene observed during the reproductive cycle. The steady-state level of mammary transferrin m…
Hepatic amino acid uptake is decreased in lactating rats. In vivo and in vitro studies.
1994
To study the redistribution of amino acids to the mammary gland during lactation we used lactating and virgin rats fed liquid diets. Virgin rats were divided in two groups: one group was fed daily a diet containing the same amount of protein that was consumed the previous day by lactating rats (high protein diet-fed rats), and the other virgin group was fed the normal liquid diet (control). The hepatic availability of amino acids was significantly higher in the lactating rats than in the other two groups, but the uptake and fractional extraction of amino acids by the liver were lower in lactating rats than in the high protein-fed virgin controls. When primary hepatocyte cultures were used, …
Regulation by oestrogens of tachykinin NK3 receptor expression in the rat uterus.
1997
The expression of the tachykinin NK3 receptor and its regulation by ovarian steroids were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) in uteri from ovariectomized rats. A single transcript corresponding to the 325-bp product expected for the tachykinin NK3 receptor was detected in uteri from olive oil-treated (control) ovariectomized rats. The level of tachykinin NK3 receptor mRNA in progesterone-treated animals was similar to that observed in uteri from control ones. Tachykinin NK3 receptor mRNA levels were significantly smaller in uteri from oestrogen-treated ovariectomized rats, with approximately a 32-fold decrease. These findings suggest that oestrogen, but not…
Atrial natriuretic peptide secretion during development of the rat supraoptic nucleus
2009
Since a relationship between atrial natriuretic peptide and oxytocin was recently demonstrated in the heart (Gutkowska et al., 1997), the aim of this study was to determine whether a relationship between the two peptides is present also in the rat hypothalamus. For this purpose, we measured ANP-ontogeny in the rat hypothalamus immunohistochemically and compared it with oxytocin-ontogeny which we previously studied. The results showed that the ANP-peptide and mRNA-ANP start at the 18th day of the fetal life. Our earlier data for oxytocin in the rat hypothalamus showed that only mRNA-oxytocin appeared the 18th day of foetal life (Farina Lipari et al., 2001); thus, at the 18th day of foetal li…
The extent of adhesion induction through electrocoagulation and suturing in an experimental rat study.
2008
Objective To investigate the effect of three types of peritoneal trauma occurring during surgery (high-frequency bipolar current, suturing, and mechanical damage) on postoperative adhesion formation in a rodent animal model. Design Randomized, controlled experimental trial in an in vitro animal model. Setting Laboratory facilities of a university department of obstetrics and gynecology. Animal(s) Thirty-five female Wistar rats. Intervention(s) Bilateral experimental lesions were created on the abdominal wall in every animal. The effect of minimal electrocoagulation was examined by creating lesions (n = 14) through sweeps of a bipolar forceps with a duration of 1 second and standardized pres…
One or two ligatures inducing periodontitis are sufficient to cause fatty liver
2017
Background Periodontitis is a chronic disease that due to an intense inflammatory response triggers systemic changes such as hepatic alterations. This study aimed to compare hepatic damage in rats that received experimental periodontitis at one or two periodontal sites with ligatures. Material and Methods Eighteen rats were separated into three groups: control, without ligature; periodontitis 1, with one ligature; and periodontitis 2, with two ligatures. The following parameters were assessed: gingival bleeding index, probing pocket depth, tooth mobility, alveolar bone loss, malondialdehyde (MDA) and myeloperoxidase (MPO) activity in periodontal tissue; histopathological evaluation of hepat…
The Effects of Epinine on Arterial Blood Pressure and Regional Vascular Resistances in Anesthetized Rats
1998
1. We carried out experiments in anesthetized rats to study the hemodynamic effects of intravenous injections of epinine. 2. Epinine (1-320 micrograms/kg) produced a biphasic effect on mean arterial blood pressure (n = 30). At doses lower than 40 micrograms/kg, arterial blood pressure decreased (by as much as 21.5 +/- 3.4%), though at higher doses it increased dose dependently (by as much as 73.2 +/- 14.5%). Epinine also produced bradicardia in a dose-dependent manner (by as much as 26.4 +/- 4.9%). Sulpiride (100 micrograms/kg) suppressed the hypotensive effect of epinine but did not change the hypertensive effect. In the presence of prazosin (1,000 micrograms/kg), arterial blood pressure r…