ABSTRACT
A significant delay in benz(A)pyrene-induced tumorigenesis was obtained following three series of parenteral injection of xenogenic leukocytic interferon alternating with irradiation at 3-4 day intervals. Radiation was delivered from a red low-energy laser through a puncture in the peritoneal wall of the spleen. When each of said procedures was performed separately similar effects were recorded but the changes were not significant.
Subject(s)
Antineoplastic Agents/pharmacology , Interferons/pharmacology , Laser Therapy , Neoplasms, Experimental/prevention & control , Animals , Benzo(a)pyrene , Carcinogens , Combined Modality Therapy , Dose-Response Relationship, Radiation , Mice , Neoplasms, Experimental/chemically induced , Neoplasms, Experimental/drug therapy , Neoplasms, Experimental/radiotherapyABSTRACT
In anesthetized dogs with natural breathing, embolisation of pulmonary arterial bed increased systolic pressure in the right ventricle of the heart up to 60.0-113.0 mm Hg. Within 6 hrs the pressure far exceeded initial and control parameters in the minor circulation circle. Tachycardia and tachypnea as well as a reduction of the left ventricle contractions and a decrease of arterial pressure occurred. The massive emboli was followed by an obvious hypoxia and an insignificant hypocapnia with no essential shifts in the blood acid-base balance. Subsequent interstitial oedema of pulmonary tissue may be due both to the changes in the lung hemodynamics and to direct damaging of endothelium in the microvessels.
Subject(s)
Disease Models, Animal , Pulmonary Embolism/physiopathology , Acute Disease , Animals , Blood Pressure/physiology , Cardiac Catheterization , Dogs , Electrocardiography , Female , Lung/physiopathology , Lung/ultrastructure , Male , Myocardial Contraction/physiology , Pulmonary Embolism/etiology , Respiratory Mechanics/physiology , Time FactorsSubject(s)
Heart/physiology , Physical Conditioning, Animal , Animals , Animals, Newborn , Electrocardiography , Female , Male , Rats , SwimmingABSTRACT
The mechanism of duodenal motor activity stimulation has been studied in dogs during irritation of the chest area of the greater splanchnic nerve. It has been established that a stimulating effect of the splanchnic nerve was not removed either by bilateral vagotomy or by separate and combined injections of bretylium tosylate and benzohexamethonium, but was removed by the blockade of M-serotoninergic receptors of the autonomic ganglia with atropine or by the blockade of D-serotoninergic receptors of the smooth muscles with promethazine hydrochloride. The data obtained demonstrate the presence of noncholinergic and nonadrenergic fibers in the chest area of the greater splanchnic nerve, having a potent stimulating effect on duodenal contractions. According to our functional and biochemical tests, they are mediated by serotonin.
Subject(s)
Duodenum/physiology , Splanchnic Nerves/physiology , Animals , Dogs , Female , Male , PeristalsisABSTRACT
The activating effect of the splanchnic nerve on motor activity of the gastro-intestinal tract could not be eliminated either with bilateral vagotomy or separate or joint administration of ornid and benzohexonium, but could be well prevented with atropin blockade of the vegetative ganglia M-serotoninergic receptors as well as diprazin blockade of the smooth muscle D-serotoninergic receptors. The data obtained reveal non-cholinergic and non-adrenergic fibers in the thoracic portion of the major splanchnic nerve which exert obvious activating effect on the stomach contractile function, serotonin being their transmitter.
Subject(s)
Gastrointestinal Motility , Serotonin/physiology , Splanchnic Nerves/physiology , Stomach/innervation , Animals , Dogs , Synaptic Transmission , Vagotomy , Vagus Nerve/physiologyABSTRACT
The transmembrane potentials of the contractile myocardium cells of intact heart and their response to acetylcholine were studied in adult and newborn guinea pigs by means of "swimming microelectrodes". High concentration of acetylcholine only slightly reduces the overshoot without causing changes in other parameters of the transmembrane potentials in adult animals whereas in newborn animals acetylcholine induces hyperpolarization of membrane of the contractile myocardium cells, increases the overshoot and the amplitude of the AP. In adult guinea pigs, acetylcholine prevents irreversible fibrillation whereas in newborn animals acetylcholine prevents spontaneous defibrillation.
