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H S Conjeevaram

Publications and source records attributed to H S Conjeevaram.

21 records · Page 2Linked to original sources

Gender-dependent reduction of spontaneous motor activity and growth in rats subjected to portacaval shunt.

Alterations in behavior are frequently described in rats subjected to portacaval shunt. Previous work has reported reduced spontaneous motor activity in various settings (nighttime, red light, decreased illumination) in this animal model. We investigated this phenomenon in rats of both genders subjected to portacaval shunt to determine whether our previously observed divergent growth patterns (males reduced, females unchanged) had any impact on the alterations in spontaneous motor activity in this model. Dietary intake, growth, motor activity and serum ammonia and amino acid concentrations were measured, in addition to final liver and spleen weights, in each animal after 3 to 4 wk of observation. Our results reconfirm the differential impact of portacaval shunt on growth in male (35% reduction p < 0.01) but not female rats (5% reduction, NS) compared with their respective-gender sham-operated controls. In addition, spontaneous motor activity was significantly reduced in male (congruent to 50%, p = 0.01) but not female rats subjected to portacaval shunt. The reduction of activity in male rats subjected to portacaval shunt did not correlate with any of the measured biochemical data or calculated nutritional/growth parameters. Thus we observed gender-dependent reduction in spontaneous motor activity after portacaval shunt in the rat. The mechanism for this phenomenon is unknown, but it is easily investigated with this reproducible model.

Amino Acids↗

Studies of "endogenous" benzodiazepine in human hepatic encephalopathy.

As will be discussed by Dr E.A. Jones based on observations in animal models of hepatic encephalopathy (HE) in 1984 we commenced our studies on the possible role of "endogenous" benzodiazepines (BZs) in human HE in 1986. Unlike animals our initial studies in humans with HE were complicated by the frequent intake of prescription BZs by these patients. Re-education of our staff on the appropriate use of BZs in patients with liver disease and a carefully devised system to exclude patients who have received prescription BZs in the 3 months preceding hospital admission was instigated before our studies could commence. Initially, we examined CSF of patients with HE for the presence of BZ-like activity using a radiometric assay. Our findings of significantly increased activity have since been confirmed by other investigators. Subsequently we discovered fairly large quantities of BZs in blood and urine of these patients, the level of which correlated with the degree of severity of HE. The ultimate finding that this BZ-like activity was due to diazepam, desmethyldiazepam and some other 1-4 benzodiazepine compounds again raised the possibility that our findings were due to occult ingestion of commercially synthesized BZs even though similar findings were made in animal models of HE. Concurrently with this work it became apparent that the food cycle contains trace amounts of the same BZs. However, the levels of "natural BZs" in food cannot yet explain the high levels of BZs seen in patients with HE. The source for this high level of BZs is currently our main area of research.

Animals↗