The response of diterpene sclareol glycol to acute hypoxia in mice.

The effects of a reversible activator of adenylate cyclase sclareol glycol (SG), a semisynthetic diterpene of the labdane family, on acute hypoxia (asphyctic, hemic-induced by 300 mg/kg of sodium nitrite injected subcutaneously, and histotoxic-induced by 20 mg/kg sodium nitroprusside injected intraperitoneally) in mice were studied. SG was applied at doses well below the lethal dose. SG increased the latency to convulsions and the survival time to death.

Effect of calcium influx blocker verapamil on adriamycin-induced cytotoxicity in leukemia cells in vitro.

The effect of verapamil (calcium influx blocker) on adriamycin-induced cytotoxicity against sensitive and resistant subline of K 562 acute myelogenous human leukemia cells has been evaluated. Verapamil by itself at a concentration of 0.5 microgram/ml did not affect the cell growth.

Effect of beta-adrenergic and serotoninergic agents on the stress-induced behaviour of "learned helplessness" in rats.

The phenomenon of "learned helplessness" is characterized by elements of motor, cognitive and emotional deficit, and it is particularly suitable to be used as a "model" of behavioural depression. There is no doubt about the central role of the cerebral noradrenaline and serotonin in the stress-induced behavioural deficit. The effects of two known beta-adrenoceptor agonists--salbutamol and trimetoquinol--and the beta-adrenergic blockers propranolol and compound 3B, with beta-blocking activity equipotent to that of propranolol, were investigated under conditions of "prophylactic" and "therapeutic" administration in rats subjected to stress by modelling of the behaviour of learned helplessness.

Central temperature effects of the transmitter amino acids.

Experiments were carried out to determine the temperature changes induced by the transmitter amino acids gamma-aminobutyric acid (GABA), taurine and glycine (representatives of the inhibitor class of amino acids), and of L-glutamic acid and L-aspartic acid (representatives of the excitatory functional class of amino acids). The amino acids were introduced directly into the preoptic anterial part of the hypothalamus (PO/AH). The experiments were made on male Wistar rats into which cannules were implanted in advance in PO/AH using a stereotaxic apparatus and coordinates of administration after König and Klippel.

Studies of the thyrotropic function of the adenopituitary of the offspring of rats treated during pregnancy with dopaminergic agents.

The thyrotropic function of the adenopituitary of rats, which were the offspring of animals treated during pregnancy with L-DOPA, bromocriptine and haloperidol, was studied. The agents were administered according to a schedule between the 1st and the 20th day of gestation--orally for L-DOPA and bromocriptine, and intramuscularly for haloperidol--on 3-month old pregnant Wistar rats. The studies on the thyrotropic function of the pituitary were carried out on the offspring of male rats reaching sexual maturity at the age of three months at a temperature of 20 +/- 2 degrees C and with cold treatment for 60 min at 4 degrees C.