Experimental Lyme disease in rabbits: spirochetes found in erythema migrans and blood.

In attempts to produce experimental Lyme disease, 33 rabbits were inoculated with Lyme spirochetes by tick feeding or from tick organ homogenates or cultures. Two rabbits developed erythema chronicum migrans at the site of inoculation, in one instance 2 days after injection of a tick organ homogenate and in the other instance, 17 days after feeding of infected Ixodes dammini ticks. Spirochetes were seen in skin biopsy specimens of the second lesion with Warthin-Starry and immunoperoxidase stains. Spirochetes were also recovered from blood cultures of two additional rabbits 2 weeks post-inoculation. These findings are characteristic of early Lyme disease in humans and give additional support for the spirochetal etiology of Lyme disease.     

Work status before and after coronaryartery bypass surgery

We studied 74 patients after coronary angiography bypass graft surgery to determine what factors govern return to work. Before surgery, 31 patients worked full-time, 17 patients worked part-time and 26 patients were not working. After surgery, 32 patients worked full-time and 26 worked part-time. Post-operative chest pain, age and the period of unemployment before surgery were the significant factors in determining return to work.     

The sequence of porcine chromogranin A messenger RNA demonstrates chromogranin A can serve as the precursor for the biologically active hormone, pancreastatin

Specific oligonucleotide priming of double-stranded DNA has been employed to sequence a porcine chromogranin A adrenomedullary cDNA. Porcine chromogranin A is more than 80% identical to human, bovine, and rat chromogranin A at its deduced N- and C-termini. A 49-amino acid region of the porcine molecule is 59-71% homologous to corresponding areas of rat, bovine, and human chromogranin A, and identical to the amino acid sequence of porcine pancreastatin. The sequence is preceded by an arginine at the N-terminus and followed by a GKR sequence at the C-terminus. Thus, porcine chromogranin A can serve as the precursor for pancreastatin, a polypeptide capable of inhibiting insulin release from the endocrine pancreas and acid secretion from parietal cells of the gut.     

Distribution of immunoreactive metorphamide (adrenorphin) in discrete regions of the rat brain: Comparison with met-enkephalin-Arg-Gly-Leu

The distribution of immunoreactive (ir)-metorphamide (adrenorphin) in 101 microdissected rat brain and spinal cord regions was determined using a highly specific radioimmunoassay. The highest concentration of metorphamide in brain was found in globus pallidus (280.1 fmol/mg protein). High concentrations of ir-metorphamide (>120 fmol/mg protein) were found in 9 nuclei, including central amygdaloid nucleus, lateral preoptic area, anterior hypothalamic nucleus, hypothalamic paraventricular nucleus, interpeduncular nucleus, periaqueductal grey matter and nucleus of the solitary tract. Moderate concentrations of the peptide (between 60 and 120 fmol/mg protein) were found in 47 brain nuclei such as nucleus accumbens, bed nucleus of stria terminalis, several septal and amygdaloid nuclei, most of the hypothalamic nuclei, ventral tegmental area, red nucleus, raphe nuclei, lateral reticular nucleus, area postrema and others. Low concentrations or ir-metorphamide (<60 fmol/mg protein) were measured in 41 nuclei, e.g., cortical structures, hippocampus, caudate nucleus, thalamic nuclei, supraoptic nucleus, substantia nigra, vestibular nuclei, cerebellum (nuclei and cortex). The olfactory bulb has the lowest metorphamide concentration (5.8 fmol/mg protein). Spinal cord segments exhibit very low peptide concentrations.     

Cholecystokinin in the hypothalamo-hypophyseal system

The non-cholinergic slow excitatory postsynaptic potential (EPSP) in the guinea pig inferior mesenteric ganglion (IMG) is believed to be mediated by substance P (SP). Yet, in ganglia of guinea pigs treated with capsaicin (50, 100, or 350 mg/kg, s.c.), a compound that depletes SP from sensory neurons, slow EPSPs were only 50% smaller in amplitude than those in vehicle-treated controls; this was true at all dosages. When ganglia from capsaicin-treated animals were desensitized to SP, slow EPSP amplitude was decreased by 50% from predesensitization values. These data indicate that capsaicin does not eliminate the slow EPSP in the IMG and suggest that both SP and another transmitter are involved in co-mediating this response.     

Gonadotropin-releasing hormone (Gn-RH) in striped mullet (Mugil cephalus), milkfish (Chanos chanos), and rainbow trout (Salmo gairdneri): Comparison with salmon Gn-RH

Immunoreactive gonadotropin-releasing hormone (Gn-RH) was extracted from brains of striped mullet, milkfish, rainbow trout, and chum salmon with acetone/HCl and petroleum ether. High pressure liquid chromatography and cross-reactivity studies show mullet, milkfish, and trout brains to contain a peptide chromatographically and immunologically identical to synthetic salmon Gn-RH, while the mammalian form of Gn-RH is detectable in none of these fishes. Gn-RH is present in immature 7-month-old and 4-year-old milkfish. A second immunoreactive peptide is separable by HPLC in all the fish studied. This “early-eluting” form of Gn-RH is unlikely to be a precursor; its cross-reactivity with antisera R-42 and #185 suggests that any modification is in the C-terminal region. Several possible roles for this peptide are advanced.     

Radiohistochemical localization of insulin receptors in the adult and developing rat brain

The light microscopic localization of insulin receptors in the rat central nervous system has been investigated by means of a new autoradiographic technique. These receptors are fairly evenly distributed in the adult brain except in the olfactory bulb. There, the external plexiform layer is especially rich in them. Insulin binding sites were more heterogeneously distributed in the fetal brain and exhibited a waxing and waning during development. Highest densities were observed at 15 days of gestation.     

Selective depletion of somatostatin in rat brain by cysteamine

A single injection of cysteamine (300 mg/kg, subcutaneously) results in a 70–80% decrease in somatostatin levels in the periventricular nucleus where somatostatin-producing neurons are located and the median eminence where somatostatinergic nerve terminals are. The drug seems quite selective: no changes in levels of other neuropeptides — LH-RH, vasopressin, enkephalin, VIP, CCK — were observed in the same animals.