Shen K L, Lin M T, Chen H C
Department of Surgery, Tri-Service General Hospital, Taipei, ROC.
Pharmacology. 1988;37(1):16-23. doi: 10.1159/000138409.
Rats with portacaval shunt, although showing no changes in their spontaneous pain threshold, did display an increased sensitivity of analgesic responses to morphine injection. In addition, these portacaval-shunted animals had a lower level of spontaneous motor activity and a reduced sensitivity of locomotor stimulant responses to amphetamine administration. However, these portacaval-shunted animals displayed same thermoregulatory responses to various ambient temperatures as those of normal unoperated or sham-operated animals. Biochemical examination revealed that these portacaval-shunted animals had a higher indoleamine synthesis in both the hypothalamus and the brain stem, but had a lower catecholamine synthesis in both the hypothalamus and the corpus striatum. The data suggest that alterations in antinociceptive and locomotor stimulant responses of the portacaval-shunted animals correlate with patterns of monoamine synthesis in different brain regions (patterns that differed from those observed in normal unoperated animals or in sham-operated animals).
