PubMed Health⌕ Search

Biomedical subjects

M Kram

Publications and source records attributed to M Kram.

7 recordsLinked to original sources
PubMed1999

Decrease in stress-induced c-Fos-like immunoreactivity in the lateral septal nucleus of learned helpless rats.

Inescapable stress can induce learned helplessness in many species of animals. Learned helplessness is a phenomenon which has some behavioral and neurotransmitter analogies with human clinical depression. Stress can also induce the expression of immediate early genes, including c-fos in many areas of the central nervous system. We examined stress-induced c-Fos-like immunoreactivity (FLI) using the learned helplessness paradigm. Naive rats showed significantly higher FLI than the tested groups in all the amygdaloid regions and in the hypothalamic paraventricular nucleus. However, in the lateral septal nucleus, helpless animals showed significantly reduced FLI in response to stress, compared to the other groups. These, and other previous data, highlight the importance of the septal area in mediating behavioral responses to inescapable stress.

Animals↗
PubMed1988

Turner's syndrome and inflammatory bowel disease: a case report with immunologic studies.

A patient with Turner's syndrome who developed ulcerative colitis (UC) is reported, and reports from the literature of 16 cases of Turner's syndrome with inflammatory bowel disease (IBD) are reviewed. Most of the patients previously described had severe disease. Half of the patients had ulcerative colitis and half had Crohn's disease (CD). Of those with Crohn's, most had colonic involvement. Of note, also, half of the patients had an isochromosome for the long arm of X which usually is found in only 17% of all patients with Turner's syndrome. A high incidence of autoimmune diseases is associated with this syndrome. We demonstrate the presence of specific anticolonic antibodies in this patient and propose some possible explanations for the association of this particular chromosomal disorder with autoimmune diseases.

Adult↗
PubMed1987

Isolation of multiple normal and functionally defective forms of uridine diphosphate-glucuronosyltransferase from inbred Gunn rats.

Gunn rats are a mutant strain of Wistar rats that have unconjugated hyperbilirubinemia due to absence of hepatic uridine diphosphate-glucuronosyltransferase (UDPGT; EC. 2.4.1.17) activity toward bilirubin. We isolated five UDPGT isoforms from solubilized microsomal fractions from liver of inbred Wistar (RHA) rats and congeneic Gunn rats. UDPGT isoform V (elution pH 7.5) from Wistar (RHA) rats is active toward bilirubin and 4'-hydroxydimethylaminoazobenzene. The corresponding isoform from Gunn rat liver was enzymically inactive but exhibited normal elution pH and mobility on NaDodSO4/polyacrylamide gel electrophoresis (Mr 53,000), and was recognized by a UDPGT-specific antiserum. UDPGT isoform I (elution pH 8.7) from Wistar (RHA) and Gunn rats was active toward 4-nitrophenol. The isoform from Gunn rat liver had only 10% of normal UDPGT activity, however UDPGT activity increased to normal upon addition of 15 mM diethylnitrosamine in vitro. Isoforms II (elution pH 8.4), III (elution pH 8.0), and IV (elution pH 7.8) from Gunn rats had normal UDPGT activities, except that Isoform IV was inactive toward bilirubin.

Animals↗
PubMed1986

Replacement of liver function in rats by transplantation of microcarrier-attached hepatocytes.

Isolated hepatocytes, harvested from normal rat livers by portal vein collagenase perfusion, can be attached to collagen-coated dextran microcarriers and transplanted by intraperitoneal injection into rats. Survival and function of the transplanted hepatocytes have been demonstrated in mutant rats lacking bilirubin-uridine diphosphate glucuronosyltransferase activity (Gunn strain) and rats with inherited lack of plasma albumin (Nagase analbuminemia rat strain). This simple technique promises to be useful in the treatment of acute liver failure in humans.

Animals↗
PubMedDate not supplied

Serotonin and learned helplessness: a regional study of 5-HT1A, 5-HT2A receptors and the serotonin transport site in rat brain.

Serotonin (5-HT) plays a central role in the neurochemistry of the learned helplessness animal model of depression. Using quantitative autoradiography, we measured the density of 5-HT1A and 5-HT2A receptors and of 5-HT transport sites in medial prefrontal cortex, dorsal hippocampus, septum, hypothalamus, and amygdala in learned helpless rats, and in rats that were nonhelpless after inescapable stress, as well as in shuttlebox-tested and nonhandled controls. We found no changes in 5-HT1A receptor density among the groups in any region studied. In dorsal hippocampus, 5-HT2A receptor density was decreased in nonhelpless rats, while in amygdala 5-HT2A receptor density was decreased in both groups of stressed rats, whether helpless or nonhelpless. In the hypothalamus 5-HT2A receptor density, was decreased in helpless rats as compared to controls. In medial prefrontal cortex, the serotonin transport sites showed decreased density in helpless rats as compared to controls but not to nonhelpless rats. These findings further highlight the complexity of regional 5-HT effects in the learned helplessness animal model.

8-Hydroxy-2-(di-n-propylamino)tetralin↗