Effects ofp-chlorophenylalanine on the metabolism of serotonin from 5-hydroxytryptophan.

The effects ofD,L-ϱ-chlorophenylalanine methyl ester (PCPA-methyl ester) and two of its metabolites, 2-(ϱ-chlorophenyl)-ethylamine (PCPEA) and ϱ-chlorophenylacetic acid (PCPAA), on the metabolism of serotonin (5-HT) fromD,L-5-hydroxytryptophan (5-HTP) ware studied in vitro and in vivo using the telencephalon and brainstem of the rat. For in vivo studies and some in vitro experiments, rats were injected with either 100 mg/kg PCPA-methyl ester or saline alone on days 1, 2, and 3, and were killed on day 15. When the in vivo metabolism of 5-HT was to be studied, the saline group and the PCPA group of animals were injected with 75 μg/kg [(3)H]D,L-5-HTP 20 min before sacrificing.

A simple technique for delivering liquids directly to the mouth of an unrestrained rat.

A simple surgical procedure is described that makes it possible to deliver liquids directly into the mouth of a freely mobile rat. Data presented show that an 8% sucrose solution delivered by this technique is an effective reinforcer in a variety of simple and discriminative schedules of reinforcement.