An efficient synthesis of 3-substituted or 2,3-disubstituted 4(3H)-quinazolinones from benzoxazin-4-ones and primary amines under microwave irradiation in unsealed vessels is described.

Antibodies with high affinity and specificity for the 1,4-dihydropyridine Ca2+-channel blockers have been produced in rabbits by immunization with dihydropyridine-protein conjugates. Anti-dihydropyridine antibodies were found to specifically bind [3H]nitrendipine, [3H]-nimodipine, [3H]nisoldipine, and [3H]PN 200-110 (all 1,4-dihydropyridine Ca2+-channel blockers) with high affinity, while [3H]v...

L-Glutamic, L-aspartic acids and a number of their structural analogs, including quisqualic, kainic, ibotenic, quinolinic, and N-methyl-D-aspartic (NMDA) acids, increase inositol phospholipid hydrolysis when added to primary cultures of cerebellar granule cells, as is reflected by an enhanced formation of 3H-inositolmonophosphate (3H-IP1) in the presence of Li+. L-Glutamic acid also enhances th...

Our studies indicate that tritiated 12-O-tetradecanoylphorbol-13-acetate ([3H]TPA) produced by the reduction of the C-20 aldehyde with sodium [3H]borohydride is recognized by the same cellular site as is unlabeled 12-O-tetradecanoylphorbol-13-acetate (TPA). None of the concentrations of TPA used in these studies had an effect on the cell number and viability of human peripheral blood lymphocyte...

The N-methyl-D-aspartate receptor (NMDAR) antagonists: MK-801, phencyclidine and ketamine are open-channel blockers with limited clinical value due to psychotomimetic effects. Similarly, the psychotomimetic effects of the dextrorotatory opioids, dextromethorphan and its metabolite dextrorphan, derive from their NMDAR antagonist actions. Differences in the use dependency of blockade, however, su...

An amine-functionalized derivative of 1,3-dipropyl-8-phenylxanthine has been prepared in tritiated form as a xanthine amine congener ([3H]XAC) for use as an antagonist radioligand for adenosine receptors. [3H]XAC has higher receptor affinity, higher specific activity, lower nonspecific membrane binding, and more favorable hydrophilicity than 1,3-diethyl-8-[3H]phenylxanthine, the xanthine common...

The metabolism of [3H]vitamin D3 in hepatectomized vitamin D-deficient rats has been studied. Hepatectomy drastically disrupts vitamin D3 metabolism as revealed by prolonged high levels of [3H] vitamin D3 in the plasma compartment even 12 h after dose in contrast to sham-operated controls. Some conversion of [3H] vitamin D3 to [3H]25-hydroxyvitamin D3 was detected in hepatectomized rats, but th...

The effects of tramadol on electrocardiogram (ECG), mean electrical axis and respiratory rates were studied in adult kagani goats after intramuscular administration of tramadol at 1 mg/kg b.wt. as a prelude to its clinical use as an analgesic in veterinary practice. The ECG was monitored by standard bipolar leads and discernible electrocardiographic features were observed in lead II. The normal...