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S Sorscher

Publications and source records attributed to S Sorscher.

3 recordsLinked to original sources

Conjugated bile acid uptake by Xenopus laevis oocytes induced by microinjection with ileal Poly A+ mRNA.

Apical membranes of ileal enterocytes contain the major Na+/bile acid cotransporter activity in mammals. Microinjection of guinea pig ileal mucosal Poly A+ mRNA (25 ng) into Xenopus oocytes resulted in 22,23-3H-cholyltaurine uptake at day 3 after injection (453 fmol/oocyte-hr), while control viral mRNA (25 ng) gave an uptake rate of 133 fmol/oocyte-hr. The transport rate increased in direct relationship to the concentration of injected mRNA, cholyltaurine, or Na+ in the incubation media. Uptake of cholyltaurine using rabbit ileal mucosal Poly A+ mRNA was 3891 fmole/oocyte-hr compared to rabbit jejunal-mucosa Poly A+ mRNA (control) injections inducing 728 fmol/oocyte-hr. Such expression of the ileal Na+/bile acid cotransporter may facilitate cloning of this key mammalian gene.

Animals↗

A comparison of the effects of morphine and forced running upon the incorporation of 14-C-tyrosine into 14-C-catecholamines in mouse brain, heart and spleen.

Morphine increases both the locomotor activity of mice and the incorporation of 14-C-tyrosine into 14-C-catecholamines in the mouse brain. To determine whether a relationship exists between increases in locomotor activity and increases in catecholamine synthesis, mice were treated with either morphine (100 mg/kg i.p.) or saline and were forced to run on a treadmill (5.4 m/min). When mice were given saline and forced to run, incorporation of 14-C-tyrosine into 14-C-catecholamines was increased over control values in the heart and spleen but unchanged in the brain. When mice were given morphine, but not forced to run, the incorporation of 14-C-tyrosine into 14-C-catecholamines was increased over control values in the brain but unchanged in the heart and spleen. Morphine decreased the catecholamine content of the mouse brain but not of the heart or spleen. Forced running did not change the catecholamine content of any tissue. The differences between the effects of morphine and forced increases in locomotor activity upon the incorporation of 14-C-tyrosine into 14-C-catecholamines and upon the catecholamine content in various tissues of the mouse indicate that the effects of morphine on catecholamine synthesis are not the result of changes in locomotor activity.

Animals↗