Subject(s)
Aspirin/adverse effects , Gastric Mucosa/pathology , Intestinal Mucosa/pathology , Prostaglandins F, Synthetic/therapeutic use , Adult , Clinical Trials as Topic , Double-Blind Method , Duodenum/drug effects , Duodenum/pathology , Gastric Mucosa/drug effects , Humans , Intestinal Mucosa/drug effects , MaleABSTRACT
Endotoxic shock was induced in rabbits of either sex by IV injection of 50 micrograms/kg endotoxin (ET) extracted from E coli O-55 by Boivin's method. A polyvinyl catheter was introduced into the superior vena cava under local anesthesia 1 day prior to the experiments. We observed a rise of plasma-free fatty acids (FFA) from an initial mean value of 190 muEq/liter to a level of 290 muEq/liter within 6 h after injection of endotoxin. The increase of FFA was followed by a rise of plasma triglycerides (TG) and an increase of very low-density lipoproteins (VLDL), beginning 1-2 h later. The rise of FFA and the following increase of TG and VLDL were significantly reduced by infusion of 14 micrograms/kg X min gabexate mesilate (GM). Our results indicate that GM--in addition to its well-known proteinase inhibitory action--effects fatty acid metabolism.
Subject(s)
Fatty Acids, Nonesterified/blood , Guanidines/administration & dosage , Shock, Septic/blood , Animals , Arrhythmias, Cardiac/etiology , Arrhythmias, Cardiac/metabolism , Endotoxins/administration & dosage , Female , Gabexate , Glycerol/blood , Lipoproteins, VLDL/blood , Male , Rabbits , Shock, Septic/etiology , Triglycerides/bloodABSTRACT
Using convential mechanical and electromyographic recording methods 2 distinct types of neurogenically elicited activity can be observed in the penis retractor muslce (PRM) of Helix pomatia: (1) rhythmic, phasic contractions correlated with single or a few compound action potentials and (2) intervening, strong, prolonged contractions accompanied by sustained, high frequency electrical muscle activity. The 2 distinct types of muscle activity which seem to play a part in the normal behaviour of the PRM in the intact animal are mediated by both the central nervous system and peripheral neurons. While central neuronal structures are involved in causing the strong, prolonged contractions, the phasic activity is initiated by peripheral neuronal structures located at the proximal end of the PRM. There is evidence that the transmission of the excitation at the neuromuscular level of central and peripheral origin is mediated by ACh.
Subject(s)
Helix, Snails/physiology , Action Potentials , Animals , Central Nervous System/physiology , In Vitro Techniques , Male , Motor Neurons/physiology , Muscle Contraction , Muscle, Smooth/innervation , Muscle, Smooth/physiology , Penis/physiology , PeriodicitySubject(s)
Helix, Snails/physiology , Muscles/physiology , Penis/physiology , Snails/physiology , Animals , Brain/physiology , Electric Conductivity , Electric Stimulation , Electromyography , Male , Microscopy, Electron , Muscles/innervation , Muscles/ultrastructure , Penis/ultrastructure , Peripheral Nerves/physiologySubject(s)
Calcium/pharmacology , Helix, Snails/physiology , Muscle Contraction/drug effects , Muscles/physiology , Penis/physiology , Snails/physiology , Acetylcholine/pharmacology , Animals , Caffeine/pharmacology , Calcium/antagonists & inhibitors , Electric Conductivity , Electric Stimulation , Male , Muscles/drug effects , Muscles/ultrastructure , Penis/drug effects , Verapamil/pharmacologyABSTRACT
The contractile activity of the penis retractor muscle (PRM) of Helix pomatia is controlled by both the central nervous system (CNS) and by a peripheral neural cell cluster. In the semi-intact PRM preparation, consisting of the PRM and the peripheral cell cluster without any attached central neuron, the CNS-mediated muscle activity was shown to be mimicked by exogenously applied adenosine triphosphate (ATP). This fact, coupled with the demonstration that ATP neither excites presynaptic motor nerve terminals nor postsynaptic sites at the neuromuscular junction, but exerts its action on the peripheral neural structures, may indicate a role of ATP in the neural transmission in the peripheral ganglionic mass at the base of the PRM.
ABSTRACT
The ultrastructure of the isolated glycerinated penis retractor muscle (PRM) of Helix pomatia was investigated. The diameter distributions of thick myofilaments from birbre cross sections in the relaxed, phasic contracted, tonic contracted, and in the catch state.s show that a characteristic filament spectrum is formed in the catch state and its preceding active state. The significant structural differences are discussed in relation to earlier hypotheses related to the catch state
