Effect of bilateral adrenalectomy on catecholamine synthesis in the rat heart

The present study was carried out to investigate the possibility of local epinephrine [E] synthesis in rat cardiac tissue and to study the effect of bilateral adrenalectomy [A DX] on catecholamine synthesis. Bilateral adrenalectomy caused significant reductions of cardiac and plasma E levels but a substantial amount of E [33.3 percent] was retained in the atrium 9 days after bilateral adrenalectomy. Also, there was significant reductions in atrial norepinephrine [NE] and dopamine [DA] as well as ventricular DA. Cardiac epinephrine forming activity [EFA] was not significantly affected in ADX rats but ventricular EFA showed 42.3 percent increase compared to sham operated [SH] rats. Cardiac dopamine-B-hydroxyls [DBH] activity was increased in the atrium [31 percent] and in the ventricle [60 percent, p <0.01] of ADX rats compared to SH rats. In SH rats, decapitation increased plasma E by 61 fold but lowered plasma DA levels significantly compared to the corresponding rest values indicating that plasma DA is incorporated in the synthesis of catecholamines in the adrenal medulla. It was concluded that cardiac tissue synthesizes its own E and bilateral adrenalectomy increase the sympathetic activity, catecholamine synthesis and NE turnover

Effect of cigarette and pipe smoking on heart rate, blood pressure and urinary excretion of VMA

The effects of cigarette smoking and pipe smoking on heart rate, systolic and diastolic blood pressure and urinary excretion of VMA were studied on two groups of human volunteers. Cigarette and pipe smoking both caused significant rises of heart rate, systolic and diastolic blood pressure and increased urinary output of VMA significantly. The responses to cigarette smoking were prompt in onset and short in duration compared to the corresponding pipe smoking responses indicating that the route of nicotine absorption was different among cigarette smoking and pipe smoking groups

Crystalline isolation and physicochemical characterization of guaiacol as a major constituent of an active spasmolytic fraction of the essential oil of teucrium polium L

Following the earlier demonstration of potent spasmolytic effect on Isolated intestinal rabbit preparations by the essential oil of Teucrium polium L., the oil [obtained by steam distillation] was fractionated on thin layer chromatographic plates to 15 fractions. The spasmolytic effect of the fractions were tested on the spontaneous motility of the isolated jejunum of the rabbit. The fraction with R f0.52 was the most potent in this regard, consisting of 20% of the essential oil. Upon subjection of the active fraction to GC analysis, the sesquiterpene alcohol guaiol [constituting 33% of the fraction] and other terpenes were separated. Guaiol, in a crystalline form, was Isolated for the first time from the essential oil of Teucrium polium. The identity of guaiol was confirmed from its physicochemical properties. Guaiol was found to Inhibit the intestinal motility of isolated rabbit jejunum. The extent of inhibition was dose dependent with an ED 50 of 60 Micro M

Ramadan fasting and catecholamine excretion

The effects of Ramadan fasting on the urinary excretion of adrenaline, noradrenaline and dopamine were studied in five healthy volunteers. Ramadan fasting caused significant increases in adrenaline and dopamine excretion with no significant change in noradrenaline excretion. It is concluded that fasting causes sympathoadrenal activation to maintain normal blood sugar value