Simultaneous recording of the transpulmonary pressure and electromyogram of the diaphragm

To record the hysteresis loop and electromyogram of the diaphragm simultaneously it is recommended that a standard probe of the sort used to record the intraesophageal pressure, on which silver electrodes are mounted, be used. This method provides fuller information on the work of the respiratory muscles.Institute of Obstetrics and Gynecology, Academy of Medical Sciences of the USSR, Leningrad. (Presented by Academician of the Academy of Medical Sciences of the USSR V. G. Baranov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 1, pp. 95–96, January, 1978.     

Injection of substance P (SP) N-terminal fragment SP(1-7) into the ventral tegmental area modulates the levels of nucleus accumbens dopamine and dihydroxyphenylacetic acid in male rats during morphine withdrawal

The biologically active substance P (SP) N-terminal metabolite SP_1–7 has been reported to modulate several neural processes such as learning, locomotor activity and reaction to opioid withdrawal. Although all these processes are believed to be associated with dopaminergic transmission no evidence of an interaction between SP_1–7 and dopamine in the case of morphine withdrawal has so far been reported. Therefore, in this work we applied in vivo microdialysis to investigate the effect of SP_1–7 injection into the ventral tegmental area on dopamine release in nucleus accumbens of male rats during naloxone precipitated morphine withdrawal. The result showed that the heptapeptide enhances dopamine release and also elevates the level of the dopamine metabolite dihydroxyphenylacetic acid in this brain area. It was suggested that the observed action of the SP fragment on the dopamine system represents the underlying mechanism for a previously observed ability of SP_1–7 to counteract the aversion response to morphine withdrawal.     

Spontaneous reanastomosis between lymphatic vessels following syngeneic transplantation of the small intestine in the rat

Abstract Spontaneous lymphvascular reanastomosis (SLR) following small bowel transplantation in rats is of clinical relevance for the resorption of long chain fatty acids. Detailed morphological and molecular data concerning the process of lymphvascular reanastomosis are not available in the literature. In this study SLR was investigated using microradiology and scanning electron microscopy. Between the 8^th and 21^st postoperative days following transplantation SLR does not occur between the intestinal trunk of the transplant and the thoracic duct of the recipient. Instead, an indirect connection was observed between the inserted advential lymphatic vessels of the mesenteric artery and lymphatic vessels of the aorta or ductus deferens, which are connected with the thoracic duct.     

Pathogenesis of pancreatic perilobular necrosis in patients with liver disease.

We often see perilobular necrosis of the pancreas in patients with liver disease at autopsy. This study was undertaken to determine the frequency and the mechanism of development of pancreatic perilobular necrosis in patients with liver disease. Pancreatic perilobular necrosis was seen in 21 per cent of 261 autopsied patients: in 41 per cent of 73 autopsied patients with liver disease and in 13 per cent of 188 autopsied patients without liver disease. Moreover, splanchnic congestion was present in 90 per cent of 30 pancreatic perilobular necrosis patients with liver disease. These data indicate that patients with liver disease develop perilobular necrosis of the pancreas more often than patients without liver disease, and that the high frequency may be a sequela of splanchnic congestion; that is, congestion of the pancreas and endotoxaemia due to congestion of the gut.     

Splenic haematopoiesis in patients with cirrhosis of the liver

Summary Hitherto it has generally been assumed that splenic haematopoiesis in adult humans occurs very infrequently and is predominantly associated with haematological disorders. In the present study of patients with cirrhosis of the liver, a marked splenic haematopoiesis was a constant finding. Moreover, low-level splenic erythro- and granulopoiesis was highly prevalent even in haematologically normal controls, while splenic thrombopoiesis was conspicuously absent in both groups. We suggest that splenic haematopoiesis results from entrapment and proliferation of circulating haematopoietic precursor cells in the splenic red pulp. This would account for the presence of splenic haematopoiesis in normal controls as well as in patients with cirrhosis of the liver. In the latter, stimulation of bone marrow haematopoiesis and increased splenic pooling of haematopoietic precursor cells may contribute to the marked increase of splenic haematopoiesis observed.     

Some studies on the mechanism of action of antibodies to nerve growth factor.

The effects of antibodies to the nerve growth factor from mouse salivary gland were examined in vitro and in vivo. Treatment of explants of receptive ganglia with antibody and complement did not produce cell damage as judged by the ability of the tissue to respond to nerve growth factor. New-born mice experimentally depleted of or genetically deficient in key complement components were susceptible to the action of the antiserum.These results show that the effect of the antibody is independent of complement and are consistent with the view that it acts by neutralization of endogenous nerve growth factor.     

Extra-hypothalamic afferent inputs to the supraoptic nucleus area of the rat as determined by retrograde and anterograde tracing techniques

To detect neuronal cell bodies whose axon projects to the hypothalamic supraoptic nucleus, small volumes (10-50 nl) of 30% horseradish peroxidase or 2% fast blue solutions were pressure-injected into the area of one supraoptic nucleus of rats. Both dorsal and ventral approaches to the nucleus were used. In animals where the injection site extended beyond the limits of the supraoptic nucleus, retrogradely labelled cell bodies were found in many areas of the brain, mainly in the septum, the nucleus of the diagonal band of Broca and ventral subiculum in the limbic system; the dorsal raphe nucleus, the locus coeruleus, the nucleus of the dorsal tegmentum, the dorsal parabrachial nucleus, the nucleus of the solitary tract and the catecholaminergic A1 region in the brain stem; in the subfornical organ and the organum vasculosum of the lamina terminalis, as well as in the median preoptic nucleus. In contrast, when the site of injection was apparently restricted to the supraoptic nucleus, labelling was only clearcut in the two circumventricular organs, the median preoptic nucleus, the nucleus of the solitary tract and the A1 region. Injections of wheat germ agglutinin coupled with horseradish peroxidase (60-80 nl of a 2.5% solution) made in the septum and in the ventral subiculum anterogradely labelled fibers coursing in an area immediately adjacent to the supraoptic nucleus but not within it. In contrast, labelling within the nucleus was found following anterograde transport of tracer deposited in the A1 region and in an area that includes the nucleus of the solitary tract. Neurones located in the perinuclear area were densely labelled by small injections into the supraoptic nucleus; they may represent a relay station for some afferent inputs to the supraoptic nucleus. These results suggest that the supraoptic nucleus is influenced by the same brain areas which project to its companion within the magnocellular system, the paraventricular nucleus.     

Avoidance conditioning in rats following changes in activity of the noradrenergic and cholinergic systems of the brain

Bilateral coagulation of the ventral noradrenergic pathways of the brain in male rats of the Wistar strain disrupted the conditioned passive avoidance response after unconditioned stimulation with a current of 0.75 mA. Injecting 10 mg/kg galantamine into these rats 20 min before training and increasing the unconditioned stimulus to 3 mA improved subsequent avoidance responses. Injecting galantamine under analogous conditions into normal rats impaired this reaction. Disruption of the conditioned avoidance response following the operation may be due to a change in the intracentral interrelation of the noradrenergic and cholinergic systems of the brain.Translated from Fiziologicheskii Zhurnal SSSR imeni I. M. Sechenova, Vol. 68, No. 3, pp. 297–302, March, 1982.