Distinct expression of protein kinase C (PKC) subspecies in the central nervous system suggested that each subspecies has a distinct neural function in the processing and modulation of a variety of physiological responses to external signals. In this study, the cellular and subcellular distributions of beta I-, beta II- and gamma-subspecies of PKC were demonstrated by using subspecies-specific antibodies in the rat spinal cord. By light microscopy both gamma- and beta II-subspecies immunoreactivities were found only in neurons of the substantia gelatinosa and axons of the dorsal corticospinal tract in the spinal cord. Use of a double staining method, however, revealed that beta II-subspecies immunoreactivity was localized in the outer part of the lamina II, whereas gamma-subspecies immunoreactivity was found in the inner part of lamina II. Immunoreactive neurons containing beta I-subspecies were scattered in the substantia gelatinosa. Beta I-subspecies immunoreactivity varied in neuronal types. Furthermore, electron microscopic analysis clearly showed the subcellular distribution of these subspecies to be different from one another. Dense gamma-subspecies immunoreactivity was found in the cytoplasm except within cell organelles of the perikarya and dendrites. Some nuclei were stained as strongly as the cytoplasm and others were stained less heavily. The nucleoli had faint or no immunoreactivity. Reaction products of beta II-subspecies were located against the inner plasma membrane but not seen in the nuclei or nucleoli. Beta I-subspecies immunoreactivity appeared to be associated with the Golgi complex. No immunoreactive products of any PKC subspecies were detected in the presynaptic terminals. The different patterns of expression described above imply that individual PKC subspecies may have a specific function in modulating the neuronal activity in the different neurons of the spinal cord.

The distribution of a subspecies of protein kinase C (PKC) encoded by the P8n sequence in rat central nervous tissue was demonstrated immunocytochemically by using antibodies raised against an oligopeptide having a partial sequence specific for the p& PKC. The pn PKC immunoreactivity was widely but discretely distributed in the brain. The distribution of the Pu PKC immunoreactivity differed from that of the P1 and y PKC subspecies. The PHn PKC immunoreactivity was found in the perikarya, dendrites, and axons of neuronal cells. Few if any glial cells were stained. Immunoreactive neurons were present in the anterior olfactory nucleus, olfactory tubercle, amygdaloid complex, caudate-putamen, accumbens nucleus, claustrum, dorsal part of the lateral septal nucleus, CA1 region of the hippocampus, subiculum, medial habenular nucleus, cerebral cortex, nucleus of the spinal tract of the trigeminal nerve, nucleus of the solitary tract, and substantia gelatinosa of the spinal cord. In these neurons, the PI PKC immunoreactivity was seen mainly in the form of cytoplasmic dots and, in some cases, diffusely in the cytoplasm. Under electron microscopy, these immunoreactive large dots appeared to be associated with the Golgi complex, suggesting that the PBII PKC plays a specialized function at the Golgi complex in certain neuronal cell types.Protein kinase C (PKC), which is activated by 1,2-diacylglycerol in the presence of Ca2l and phospholipids, acts as a key enzyme for signal transduction in various physiological processes (1-3). Recent molecular cloning studies have revealed that PKC is a large family consisting of at least seven subspecies (a, 1 PI, y, 8, E, and O) with closely related but distinct structures (3). Enzymological studies have shown that PKC can be resolved into three distinct fractions, types I-III, by hydroxyapatite column chromatography (4). Comparison of these fractions with the enzymes expressed in COS-7 cells transfected by the respective cDNA-containing plasmids (5, 6) has indicated that PKC types I, II, and III are products of y, f, and a genes, respectively. Distribution of these three subspecies has been studied by biochemical and immunocytochemical procedures (7-13). The y (type I) PKC is found only in the neurons of the central nervous system, whereas the P8 and PII (type II) PKC and a (type III) PKC are detected in both central and peripheral tissues (7,(14)(15)(16) MATERIALS AND METHODS Production of Antibodies Against Pu Subspecies of PKC.The carboxyl-terminal portion of the PI, PKC (residues 660-673: Ser-Phe-Val-Asn-Ser-Glu-Phe-Leu-Lys-Pro-Glu-ValLys-Ser) was selected as an amino acid sequence specific to the PII PKC. The oligopeptide was synthesized and coupled to bovine serum albumin by glutaraldehyde (17). The product was mixed with complete Freund's adjuvant and injected intracutaneously into rabbits. The antigen, emulsified with incomplete Freund's adjuvant, was injected repeatedly at intervals of 2 weeks, and the rabbits were bled 4-6 days after each booster injection. The titer ...

Ethylenediaminetetraacetic acid-dependent pseudothrombocytopenia (EDTA-PTCP) is the phenomenon of a spurious low platelet count due to antiplatelet antibodies that cause platelet clumping in blood anticoagulated with EDTA. We describe a case of EDTA-PTCP that appeared transiently with the development of sepsis. A 50-year-old man underwent Bentall's aortic root replacement for acute aortic dissection with aortic insufficiency. Postoperatively the patient suffered paralytic ileus followed by methicillin-resistant Staphylococcus aureus enteritis and septicemia with endotoxemia. EDTA-PTCP appeared with the development of sepsis, and disappeared with its resolution. To avoid incorrect diagnoses and inappropriate treatment, EDTA-PTCP should always be considered as a possible cause of reported low platelet counts, even in patients with sepsis.

ABSTRACT. Studies were performed on isolated pulmonary arterial segments to investigate dopamine receptormediated relaxant effects at different times during development. Dopamine receptor-mediated relaxant effects can only be observed when vessels are precontracted with prostaglandin Fz, and in the presence of al, ag P, and serotonergic blockade. Helical strips of pulmonary arteries from rabbits of different ages (2, 7, 14, 30, and 90 days), partially precontracted by prostaglandin Fz, were tested for their responses to dopamine in the presence of prazosin M), yohimbin M), propranolol M), and methysergide M). Strips from 2-and 7-day-old rabbits were not induced to relax by dopamine, whereas those from 14-, 30-, and 90-day-old animals, after cumulative application of dopamine, underwent concentration-dependent relaxation. Dopamine (half the maximum response) concentration decreased during the development of rabbits from 14 to 90 days old. Mean values for apparent dopamine ED50 (half the maximum response) concentrations in the arteries of 14-, 30-, and 90-day old animals were 4.94 + 0.40, 2.02 + 0.30, and 0.113 + 0.028 wM, respectively.The effects of various dopamine antagonists on dopamineinduced relaxation were not markedly different at different ages. These findings indicate that dopamine receptor function is not fully developed in the pulmonary arteries of newborn rabbits, but matures as the age of the rabbit increases. (Pediatr Res 24: 160-165, 1988) Abbreviations ED50 concentration, concentration that produced half the maximum response pAz value, the negative logarithm of the molar concentration of the antagonist that produces a 2-fold shift to the right of the dose-response curve for the agonist Dopamine stimulates PI-adrenergic receptors causing positive inotropy and has been used to treat shock and congestive heart failure. In high doses, it also stimulates al-adrenergic receptors causing vasoconstriction. In low doses, however, specific dopaminergic receptors mediate vasodilation.In the cardiovascular system specific dopaminergic receptors are found in renal, mesenteric, splenic, coronary, cerebral, and femoral arteries. A vascular dopaminergic receptor classification has been proposed by Goldberg and Kohli (1, 2), in which the DA, receptor subserves smooth muscle relaxation, and the DA2 Received December 29, 1987; accepted March 18, 1988. Correspondence Dr. Miyako Mori, Department of Anesthesiology, Kobe University School of Medicine, Kusunoki-cho-7, Chuo-ku, Kobe, 650 Japan.Supported by grants from the Ministry of Education, Japan.receptor subserves the inhibition of noradrenaline release from postganglionic sympathetic nerves. Previously, we confirmed the existence of DAI dopamine receptors in the adult rabbit pulmonary artery (3). Dopamine produced a concentration-dependent relaxation of arterial strips contracted with prostaglandin F2, in the presence of prazosin (al-blocker), yohimbin (a2-blocker), propranolol (P-blocker), and methysergide (serotonin-blocker). The pulmonary circulatory system un...

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