Co-administration of melatonin reverses the tin-protoporphyrin (SnPP) induced decline of cytochrome P450 content in vivo in rats.

Melatonin (N-acetyl-5 methoxytryptamine) is a low molecular weight antioxidant and is an endogeneous defense system against the deleterious actions of the extremely reactive hydroxyl radical. Among the enzymes that participate in the antioxidant functions is cytochrome P-450, a stalwart of the detoxification system in the body. Our results revealed that tin-protoporphyrin administration brought about a marked decline in cytochrome P-450 levels. This decline was, however, reversed by the coadministration of the antioxidant, melatonin. Thus, the enhanced antioxidant status in melatonin-treated rats may act as a protective mediator of various pharmacological functions altered during tin-protoporphyrin (an antihyperbilirubemenic agent) administration to Wistar rats.

Prediction of some ventilatory 'norms' in healthy Indian males 21-69 years age.

This paper presents regression equations for predicting some ventilatory 'norms' (viz. vital capacity, forced vital capacity, forced expiratory volume for one second, expiratory reserve volume, inspiratory capacity and maximum voluntary ventilation) from physical characteristics of healthy Indian males. These equations have been constructed on the basis of multivariate regression analysis of the data of ventilatory 'norms' and physical characteristics collected on 171 healthy Indian males of age ranging from 21-69 years. Applications of these regression equations will be of practiced importance to biomedical scientists interested in the indirect assessment of ventilatory 'norms for a wider age range (21-69 years) which has not been covered by earlier studies carried out in this direction.

Cadmium, carcinogen, co-carcinogen and anti carcinogen.

As a stress agent, inducing apoptosis and blocking it, Cd can have both helpful and harmful effects. The atmosphere is a thin envelope which makes the worid a global village. Cd is the most toxic metal in air. As both the first and second messenger of the stress response, it is synergistically toxic with all other stressors, including many other carcinogens. Elimination of Pb and its replacement with added benzene in gasoline appears to have increased the toxicity of atmospheric Cd. With scientific understanding of the molecular basis of Cd's role in carcinogenesis and anti-carcinogenesis, primary cancer prevention can be practiced by reducing Cd and chemical air pollution and educating the public on smoke cessation, healthy eating habits and stress reduction. Using the existing information on Cd and its effects, determinations could be made on established cancers so that individualized treatment protocols can be developed to improve patient care.

Inhibitory effect of metalloporphyrins in conjunction with cholesterol on hepatic phospholipase A(2) activityin vivo in rats.

We investigated the effect of cholesterol and the metalloporphyrins cobalt mesoporphyrin (CoMP) and chromium protoporphyrin (CrPP) on phospholipase A(2) (PLA(2)) activity and the consequent hepatic mitochondrial stability as well as on lipid concentrations. Our studies revealed that on administration of cholesterol, CrPP, CoMP as well as simultaneous adminstration of cholesterol and CrPP, there was an inhibition of PLA(2) activity. These moieties may therefore, be agents for preventing destabilisation of the mitochondrial membrane and the consequent pathological conditions which may arise due to membrane lysis. Our results revealed that cholesterol administration increased phospholipid concentration, albeit by modest amounts. Although the independent administration of metalloporphyrins led only to minor elevations in phospholipid concentration, the simultaneous administration of cholesterol and CrPP generated a steep elevation in the concentration of total phospholipid. Since cholesterol inhibits PLA(2) activity it has the potential of being therapeutic agent for preventing the pathological conditions which may arise due to membrane lysis.

Antagonistic effect of FePP on the ethanol mediated induction of hepatic, renal and splenic δ-amino levulinic acid synthase activityin vivo in rats.

In the current study, we report perturbations in hepatic, renal and splenic heme synthesis at the level of the rate limiting enzyme, δ-amino levulinic acid synthase (ALA-S) on ethanol administration independently and in conjunction with iron-protoporphyrin (FePP) in male Wistar rats. Excessive ethanol administration (5 ml/kg bw) resulted in a significant induction of hepatic, splenic and renal ALA-S activity. Simultaneous administration of FePP (50 µmol/kg bw) reverted the observed induction response to a sharp decline. The features of the action of ethanol and FePP togetherin vivo, i.e. a substantial inhibition of ALA-S is suggestive of the beneficial effects of this formulation in acute attacks of porphyria.

An opium alkaloid-papaverine ameliorates ethanol-induced hepatotoxicity: Diminution of oxidative stress.

In this communication, we show the modulatory potential of papaverine, an opium alkaloid and a well known vasodilator agent on the ethanol-induced hepatic oxidative stress in male Wistar rats. Ethanol treatment (50% v/v) enhanced lipid peroxidation significantly accompanied by a decline in the activities of glutathione peroxidase (G-Px), glutathione reductase (GR) and depletion in levels of hepatic glutathione (GSH). Ethanol administration increased hepatic glutathione-s-transferases (GST). Enhanced lipid peroxidation induced by ethanol was significantly reduced when papverine was coadministered (P<0.05). In addition, the depleted levels of glutathione and inhibited activities of G-Px and GR recovered significantly (P<0.05) levelling off to control values on co-exposure. Papaverine (200 mg/kg bw) effectively antagonised the ethanol-induced lipid peroxidation and impaired glutathione levels and glutathione dependent enzyme systems. Our results suggest that papaverine is an effective chemopreventive agent in the liver and may suppress the ethanol-induced hepatotoxicity.

CAUDAL ANALGESIA FOR POSTOPERATIVE PAIN RELIEF IN CHILDREN.

Postoperative pain relief in 40 children undergoing elective infraumbilical surgery was assessed after caudal epidural adminstration of either lignocaine or bupivacaine in the doses of 0.5 mL/kg body weight of a 1 per cent solution and 0.5 mL/kg body weight of a 0.25 per cent solution respectively. Pain free period was assessed by subjective pain scales. The pain free period was significantly prolonged in children who were given bupivacaine (14.75 ± 2.75 hours) as compared to lignocaine (7.25 ± 3.25 hours).