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Allergy to guinea pigs: II Identification of specific allergens in guinea pig dust by crossed radio-immunoelectrophoresis and investigation of the possible origin.

An extract of dust from the air-vent filters of a room housing guinea pigs was analysed by quantitative immunoelectrophoretic procedures and compared with extracts of various materials derived from guinea pigs. Crossed radio-immunoelectrophoresis (CRIE) of the dust, performed with sera from twenty asthmatic patients who were positive by skin testing and RAST to guinea pig extracts, identified fourteen IgE-binding constituents. Although responses varied, most sera reacted with four particular allergens, antigens 2, 3, 10 and Sl. The numbers of allergens recognized by individual patients correlated with the RAST score, but not with total serum IgE. All seventeen dust constituents detected by crossed immunoelectrophoresis (and all four major allergens), were also present in extracts of guinea pig dander, fur, saliva and urine; several of these components were absent in an epithelial extract, and there were even less in preparations of shaved pelt, serum or faeces. None of the dust extract antigens were detected in materials used in animal husbandry, dust samples from rooms without guinea pigs, or a D. pteronyssinus extract. These findings suggest that inhalant allergens may be derived predominantly from material shed from the guinea pig coat after contamination with saliva, and possibly to a lesser extent, urine.

Allergens↗

Studies on the pathogenesis of experimental autoimmune renal tubulointerstitial disease in guinea pigs. VI. Induction of renal lesions by active or passive immunization of strain 2 guinea pigs.

It has been reported that strain 2 guinea pigs do not develop experimental autoimmune renal tubulointerstitial disease (RTD) by active or passive immunization. Under our experimental conditions strain 2 guinea pigs are susceptible to the induction of RTD. Typical moderate to severe renal lesions were seen 22 days after immunization with rabbit tubular basement membrane in complete Freund's adjuvant. Most Albany strain guinea pigs had severe RTD. Susceptibility to induction of RTD by passive transfer of antitubular basement membrane autoantibodies was studied in Albany (A) and strain 2 (2) guinea pigs, as well as in A leads to A, A leads to 2, and 2 leads to A radiation chimeras. Only some strain 2 guinea pigs had mild to severe renal lesions by day 9, but by day 19 all had typical histologic renal abnormalities. Albany guinea pigs already had moderate to severe RTD by days 9-10. Strain 2 differed from Albany recipients by a noticeable delay in the onset of lesions. Bone marrow transplants between Albany and strain 2 did not affect these susceptibility differences. A leads to 2 recipients responded like strain 2, and 2 leads to A like Albany. This indicates that the delay of onset of RTD in strain 2 is not a defect in the bone marrow-derived inflammatory cells.

Animals↗

Immunocytochemical detection of B cells in the guinea pig pancreas using guinea pig antiserum to porcine insulin.

The purpose of this study was to determine if antisera to an heterologous insulin could replace specific anti-guinea pig insulin serum for immunoperoxidase localization of guinea pig B cells. We found that antisera to porcine insulin was effective for this purpose even though it was produced by guinea pigs. The immunostaining results obtained with anti-porcine insulin sera and anti-guinea pig insulin serum were identical, by both light and electron microscopic immunoperoxidase staining. Control experiments supported the conclusion that the guinea pig antisera to porcine insulin contained antibodies that reacted with guinea pig insulin.

Animals↗

Characterization of an antiserum to guinea pig antithrombin III (AT III). I. Reactivity with guinea pig T lymphocytes.

In the course of studies investigating the effects of antisera prepared against a variety of guinea pig proteins on lymphocyte function, a goat antiserum prepared against a guinea pig gamma-globulin preparation was found to react with guinea pig T lymphocytes. This antiserum, serum 592, contained a significant titer of antibodies that were cytotoxic for a subpopulation of lymph node cells and thymocytes, and mitogenic for lymph node T cells. Immunoelectrophoretic analysis and selective absorptions of the antiserum demonstrated that the antigen recognized on thymocytes was also present on an alpha 2 globulin in guinea pig plasma, which, on the basis of physiochemical characteristics and heparin-binding affinity, appeared to be guinea pig antithrombin III (AT III). Although the antiserum was shown to contain antibodies to both protein and carbohydrate determinants on the AT III molecule, studies comparing the effects of 7 M guanidine and periodate oxidation on the antigenicity of the AT III determinant also recognized on the thymocytes indicated that this shared antigenic determinant was carbohydrate in nature. The thymocyte membrane molecule bearing this determinant was also isolated and was found to be a 210,000-dalton macromolecule that was very sensitive to proteolytic and/or autolytic degradation. These data raise the interesting possibility that guinea pig lymphoid cells may have a membrane-associated protease inhibitor related to plasma AT III.

Animals↗

A monoclonal antibody that blocks the complement regulatory activity of guinea pig erythrocytes and characterization of the antigen involved as guinea pig decay-accelerating factor.

MCA44 is a mAb with the capacity to sensitize neuraminidase-treated guinea pig E for hemolysis by homologous guinea pig C, and the Fab fragments of this mAb could also sensitize guinea pig E interfering with the function of a membrane inhibitor of C on guinea pig E. Using an immunosorbent column to which MCA44 was coupled, the antigenic molecule termed 44Ag was purified from the glycoprotein fraction extracted from E membranes. C intermediate sheep E treated with guinea pig C1 and C4 after sensitization with Ab (EAC14b cells) lost the ability to generate C3 convertase with C2 after incubation with 44Ag. Treatment of guinea pig E and PBL with phosphatidyl-inositol specific phospholipase C (PIPLC) partially removed 44Ag, as determined by flow cytometric analysis after immunofluorescence staining with MCA44. However, 125I-labeled 44Ag adsorbed to human E was efficiently removed by PIPLC treatment with a slight reduction in M(r). The 44Ag purified on an immunosorbent column showed three bands on SDS-PAGE. However, partial N-terminal amino acid sequences of the 55-kDa, 70-kDa, and 88-kDa bands under nonreducing conditions were identical and the sequence was 55% homologous to the N-terminal sequence of human decay accelerating factor (CD55). Intracutaneous administration of MCA44 or its F(ab')2 fragment resulted in increased capillary permeability, even after 3 days, as determined by the appearance of Evans blue spots after i.v. administration of the dye. Because control Abs including anti-class I-MHC did not cause such increased capillary permeability, the increase in permeability caused by MCA44 was likely induced by blocking the function of 44Ag in vivo, indicating a crucial role for these molecules in preventing over-activation of C at the site.

Amino Acid Sequence↗

Inhibition of some aspects of acute inflammation of guinea-pig lung by intraperitoneal dexamethasone and mifepristone: demonstration of agonist activity of mifepristone in the guinea-pig.

We have determined the inhibitory activity of dexamethasone as an inhibitor of histamine-induced plasma protein extravasation (PPE) in guinea-pig lung and skin, and of lipopolysaccharide (LPS)-induced neutrophilia and platelet activating factor (PAF)-induced eosinophilia in guinea-pig lungs. Dexamethasone inhibited PAF-induced eosinophilia in guinea-pig lung (ED50 1.4 mg/kg i.p.). Higher doses of dexamethasone were required to inhibit LPS-induced neutrophilia (ED50 10.8 mg/kg i.p.). However, at doses up to 150 mg/kg i.p. dexamethasone did not inhibit histamine-induced plasma protein extravasation (PPE) in guinea-pig lung, but did inhibit PPE in guinea-pig skin. These preparations have previously been shown to be equally sensitive to inhibition by the beta 2-adrenoceptor agonist salmeterol. Dexamethasone inhibited PAF-induced eosinophilia (5 mg/kg) or LPS-induced neutrophilia (50 mg/kg) when given 3 h or 1 h prior to challenge. Inhibitory activity was lost when dexamethasone was administered 23 h prior to LPS or 1 h after PAF. The glucocorticoid antagonist mifepristone (1-100 mg/kg i.p.) caused dose-related inhibition of PAF-induced eosinophilia but not of LPS-induced neutrophilia. The highest dose of mifepristone used (100 mg/kg) did not reverse the inhibitory actions of dexamethasone (50 mg/kg) on LPS-induced neutrophilia. We suggest that the different inhibitory activity of dexamethasone in the preparations studied indicates differences in the sensitivity of the target cells involved to inhibition by dexamethasone. We also suggest that inhibition of PAF-induced eosinophilia by mifepristone reflects the partial agonist activity of this agent, demonstrated by others in different experimental systems.

Acute Disease↗

Involvement of the M2 muscarinic receptor in contractions of the guinea pig trachea, guinea pig esophagus, and rat fundus.

The involvement of the M2 muscarinic receptor in contractile responses of the guinea pig trachea, guinea pig esophagus, and rat fundus was investigated. In the standard assay, oxotremorine-M elicited contractions of the trachea with an EC50 value of approximately 73 nanoM.--2- -(Diethylamino)methyl- -1-piperidinyl-acetyl--5,11- dihydro-6H-pyrido-2,3-b--1,4- benzodiazepine-6-one (AF-DX 116) at 1 and 10 microM antagonized these contractions by 2.1- and 9.0-fold increases in the EC50 value for oxotremorine-M. These effects are consistent with antagonism of an M3-mediated contractile response. In subsequent experiments, the M3 receptors were first inactivated selectively by incubation with N-(2-chloroethyl)-4- piperidinyl diphenylacetate (4-DAMP mustard) (40 nanoM) for 1 hr in the presence of AF-DX 116 (1 microM) followed by extensive washing. In 4-DAMP mustard treated trachea, oxotremorine-M elicited contractions with an EC50 value of 0.31 microM in the presence of histamine (10 microM) and forskolin (4 microM). Under these conditions, AF-DX 116 at 1 and 10 microM antagonized contractions to oxotremorine-M by 8- and 59-fold increases in the EC50, respectively, while para- fluorohexahydrosiladiphenidol(p-F-HHSiD) (0.1 microM) had no effect. These effects are consistent with a contraction being mediated by an M2 receptor. In the guinea pig esophagus and rat fundus, AF-DX 116 and p-F-HHSiD blocked contractions measured under similar conditions with magnitudes intermediate between what would be expected from an M2 and an M3 receptor, suggesting that perhaps both subtypes contribute to the overall contractile response under these conditions. In addition, contractions of the guinea pig trachea measured in the presence of histamine and forskolin were pertussis toxin sensitive. These results that, in the trachea, M2 receptors can dominate the contractile response after a majority of the M3 receptors have been inactivated, whereas in the guinea pig esophagus and rat fundus, M2 receptors may contribute to, but do not play a dominant role in the overall response.

Adrenergic beta-Agonists↗

The effect of ONO-3708, a novel TxA2 receptor antagonist, on U-46619-induced contraction of guinea pig and human tracheal strips in vitro and on bronchoconstriction in guinea pigs in vivo.

The effect of (9, 11), (11, 12)-didedoxa-9 alpha, 11-alpha-dimethylmethano-11,12-methano-13,14-dihydro-13-aza-14-oxo -15-cyclo-pentyl-16, 17, 18, 19, 20-pentanor-15-epi-TxA2 (ONO-3708) on 9,11-methanoepoxy-prostaglandin H2 (U-46619)-induced contraction of airway smooth muscle in the guinea pigs and human in vitro and bronchoconstriction in guinea pigs in vivo was investigated. In in vitro experiments, ONO-3708 inhibited the U-46619-induced contraction of isolated guinea pig and human tracheal smooth muscle in a dose related fashion (guinea pig; pA2=7.78, human; pA2 = 7.43). The contractions of guinea pig tracheal muscle caused by histamine and leukotriene D4 (LTD4) were not inhibited by ONO-3708. In in vivo experiments, intravenous injection of ONO-3708 at doses between 1 and 20 mg/kg inhibited the U-46619-induced increase of airway insufflation pressure as measured by Konzett-Rössler method. In addition, ONO-3708 inhibited the U-46619-induced increase in airway reactivity to acetylcholine. These data suggest that ONO-3708 has possible therapeutic utility for asthma in which TxA2 participates.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗

The effect of ethylenedinitrilotetraacetic acid (EDTA) on the reaction between the guinea-pig C5 convertase and guinea-pig C5.

Guinea-pig C5 was reacted with EAC1423 in the washed-cell intermediate assay in the presence of glucose gelatin veronal buffer (GGVB), Zn2+-GGVB (0.025 mM), GGVB2+ containing Ca2+ and/or Mg2+ or EDTA (0.013 M)-GGVB. The EDTA inhibited the formation of competent SAC14235, while Ca2+ and/or Mg2+ had a slight enhancing effect compared to GGVB alone and Zn2+ gave a four-fold increase. Similar results were obtained by using human C5 with guinea-pig C5 convertase and functionally pure guinea-pig C6, C7, C8 and C9. When guinea-pig C6 was incorporated into these various reaction mixtures with guinea-pig C5, its addition markedly reduced the inhibition by EDTA, while Zn2+ still showed an enhancing effect. These results demonstrate that EDTA inhibited formation of competent SAC14235 by preventing activation of C5. The association of C6 with C5 can partially overcome the inhibition of C5 conversion by EDTA and may account for C5 activity in reaction mixtures containing C-EDTA.

Animals↗

Comparative in vitro effects of guinea pig VIP and common VIP on liver and lung membranes from guinea pig and rat and on human lymphoblastic SUP-T1 membranes.

Guinea pig VIP differs from VIP of several mammals by its amino acids in positions 5, 9, 19 and 26. We tested a) its ability to occupy VIP receptors in liver and lung membranes of rat and guinea pig and in the human lymphoblastic SUP-T1 cell line and b) the ensuing adenylate cyclase stimulation. In liver and lung membranes from rat, guinea pig VIP was less potent than common VIP to occupy high and low affinity VIP receptors. In rat liver both VIP activated adenylate cyclase mostly through high affinity receptors. In rat lung, guinea pig VIP activated the enzyme mostly through high affinity receptors and was less efficient than common VIP acting through both classes of receptors. In guinea pig liver and lung membranes, binding inhibition curves were steeper than with rat preparations and adenylate cyclase appeared to be mostly activated through high affinity VIP receptors in liver and through both classes of receptors in lung. On human lymphoblastic SUP-T1 membranes both VIP were equally potent and efficient to inhibit tracer binding and activate adenylate cyclase.

Adenylyl Cyclases↗

Effect of thromboxane synthetase inhibitors (OKY-046, OKY-1580) on the action of bronchoactive agents in guinea pig tracheal strips and on arachidonate metabolism in guinea pig lung lobes.

We investigated the effect of the thromboxane synthetase inhibitors, OKY-046 and OKY-1580, on the action of bronchoactive agents in guinea pig tracheal strips, and on arachidonic acid metabolism in isolated perfused guinea pig lung lobes. OKY-046 and OKY-1580 attenuated histamine-, serotonin-, acetylcholine-, bradykinin- and prostaglandin F2- induced contractile responses in guinea pig tracheal strips dose-dependently and potentiated isoproterenol-, salbutamol- and prostaglandin E2-induced relaxation in guinea pig tracheal strips dose-dependently. In addition, OKY-046 and OKY-1580 inhibited the biosynthesis of thromboxane A2 and accelerated the production of 6-keto prostaglandin F1 from arachidonic acid in isolated perfused guinea pig lung lobes. The above results suggest that OKY-046 and OKY-1580 might be useful therapeutic agents for the treatment of pulmonary thromboembolism and chronic obstructive lung diseases.

Animals↗

In vitro activities of fleroxacin against clinical isolates of Legionella spp., its pharmacokinetics in guinea pigs, and use to treat guinea pigs with L. pneumophila pneumonia.

The activities of fleroxacin against 22 clinical Legionella isolates were determined by agar and broth microdilution susceptibility testing. The fleroxacin MIC required to inhibit 90% of strains tested on buffered charcoal yeast extract agar medium supplemented with 0.1% alpha-ketoglutarate was 0.64 micrograms/ml and was 0.04 microgram/ml when testing was done with buffered yeast extract broth supplemented with 0.1% alpha-ketoglutarate. Fleroxacin (0.25 microgram/ml) reduced the bacterial counts of two L. pneumophila strains grown in guinea pig alveolar macrophages by 1 log10 CFU/ml, but regrowth occurred over a 3-day period; fleroxacin was significantly more active than erythromycin in this assay. Single-dose (10 mg/kg of body weight given intraperitoneally) pharmacokinetic studies performed in guinea pigs with L. pneumophila pneumonia revealed peak levels in plasma and lungs to be 3.3 micrograms/ml and 3.5 micrograms/g, respectively, at 0.5 h and 0.8 microgram/ml and 0.8 microgram/g, respectively, at 1 h. The half-life of the terminal phase of elimination from plasma and lung was approximately 2 h. All 17 infected guinea pigs treated with fleroxacin (10 mg/kg/day) for 2 days survived for 14 days post-antimicrobial therapy, as did all 16 guinea pigs treated with the same dose of fleroxacin for 5 days. Only 1 of 16 animals treated with saline survived. The animals treated with fleroxacin for 2 days lost more weight and had higher temperatures than those treated with the antibiotic for 5 days. Fleroxacin is effective against L. pneumophila in vitro and in a guinea pig model of Legionnaires' disease. Fleroxacin should be evaluated as a treatment for human Legionnaires' disease.

Animals↗

Comparison of guinea pig cytomegalovirus and guinea pig herpes-like virus: pathogenesis and persistence in experimentally infected animals.

The pathogenesis of guinea pig cytomegalovirus (GPCMV) and guinea pig herpes-like virus (GPHLV) in guinea pigs was compared. Animals were inoculated with the two viruses by different routes and sacrificed after varying periods of time. GPCMV was consistently isolated from salivary gland 2 weeks postinoculation and thereafter following intraperitoneal or subcutaneous incoulaton. Virus was less frequently found in other tissues including blood, spleen, and kidney. Intranuclear inclusions were seen in tissue sections of salivary gland after inoculation with GPCMV- infected tissue suspension, but were only rarely found after inoculation with tissue culture virus. In GPHLV-infected guinea pigs, consistent latent infection of leukocytes and other tissues was detected by cocultivation techniques. Intranuclear inclusions were not found in the spleen, salivary gland, or other infected tissues after GPHLV infection with either tissue culture virus or infected tissue suspension. Guinea pigs inoculated with GPCMV produced high titers of specific neutralizing antibody to the homologous virus; those inoculated with GPHLV developed long-term viremia accompanied by minimal neutralizing antibody levels to the virus.

Animals↗

Humoral immunity in the resolution of genital infection in female guinea pigs infected with the agent of guinea pig inclusion conjunctivitis.

Female guinea pigs infected in the genital tract with the chlamydial agent of guinea pig inclusion conjunctivitis were selectively immunosuppressed by varying regimens of cyclophosphamide (Cy) treatment. Temporary suppression of both humoral and cell-mediated immunity by daily treatment of Cy (25 mg/kg) for 13 days resulted in a prolonged infection, whereas daily treatment for the duration of the experiment totally prevented the development of humoral and cell-mediated responses and produced an intense and prolonged infection which did not resolve. When humoral immunity alone was suppressed by treatment with Cy (250 and 150 mg/kg) at 9-day intervals, the infection again did not resolve. Treatment with 100 mg of Cy per kg at 9-day intervals resulted in an extended infection which resolved concomitantly with the development of antibody to guinea pig inclusion conjunctivitis. These data indicate that humoral immunity is essential for the recovery of female guinea pigs from guinea pig inclusion conjunctivitis genital infection. A market weight loss was observed which could not be attributed to Cy treatment alone. Edematous and ulcerative changes of the external genitalia were also noted.

Animals↗

Guinea pig herpes-like virus infection. I. Antibody response and virus persistence in guinea pigs after experimental infection.

Guinea pigs, experimentally infected with guinea pig herpes-like virus produced antibodies which were detectable by indirect hemagglutination (IHA), complement-fixation (CF), and neutralization tests. The IHA test appeared to be a more sensitive method than the CF or neutralization test for determining antibody response in guinea pigs immediately after infection, but the IHA method was not suitable for the detection of antibody in animals receiving small doses of virus. Antibody titers obtained by CF tests were generally higher than those obtained by the neutralization test, and they followed the same time course when individual animals were studied serially. Intracardiac inoculation produced the best antibody response in guinea pigs when compared with other routes of infection. Guinea pigs infected by the intraperitoneal, intranasal, or oral route showed rising antibody titers but the levels were low. Infectious virus was isolated from and persisted in all inoculated animals in the presence of antibody regardless of the route of inoculation. Recovery of infectious virus required cultivation or cocultivation of tissue cells containing virus. The administration of antilymphocyte sera delayed the appearance of IHA antibody but had no effect on antibodies determined by the CF- and neutralization tests.

Animals↗

Comparison of enterotoxicity between autumn crocus (Colchicum autumnale L.) and colchicine in the guinea pig and mouse : enterotoxicity in the guinea pig differs from that in the mouse.

Autumn crocus poisoning of cattle is characterized by severe diarrhea caused by alkaloid colchicine. Previously, we examined pathologically this poisoning in cattle and reported that enterotoxic lesions were closely associated with apoptosis. To examine enterotoxicity of autumn crocus more precisely, a reproductive study was performed using guinea pigs and mice, and pathological findings associated with autumn crocus poisoning were compared with those of colchicine. Each group of guinea pigs given the bulb of autumn crocus or colchicine exhibited severe diarrhea. Histopathological findings in intoxicated guinea pigs were entirely consistent with those in the autumn crocus-poisoned cattle. In contrast, each group of mice administered with the bulb or colchicine did not develop diarrhea. Our results confirmed that the toxicity of autumn crocus bulb is attributable to the toxicity of ingredient colchicine, and revealed that the guinea pig has high reproducibility of autumn crocus poisoning in cattle and colchicine poisoning in humans. It has been reported that the physiological mechanism of the apoptotic process for eliminating the enterocytes in the mouse and rat differs from that of the guinea pig, monkey, cattle and horse. Taking the observation that the former animals do not develop diarrhea, whereas the latter animals do so in the autumn crocus or colchicine poisoning into consideration, it would seem that the species-difference in enterotoxicity of autumn crocus may be closely associated with the physiological mechanism of eliminating the effete enterocytes.

Animals↗

Guinea pig histocompatibility antigens. III. Analysis of normal lymphocyte transfer (NLT) reactions among guinea pigs with serologically defined phenotypes (GPL-AB locus and I region).

The normal lymphocyte transfer (NLT) reaction occurring upon intradermal injection of lymphocytes into a normal recipient may be considered as a kind of mixed lymphocyte reaction in vivo. In previous experiments, we have defined serologically a number of guinea pig lymphocyte antigens, controlled either by a GPL-A locus (equivalent of H-2 D locus in mice) or by a so-called I region (equivalent to the I region in mice). The I region also appears to control a number of immune response genes in the guinea pig. Using guinea pig inbred strains (such as 2, 13, OM3, BE), guinea pig families homozygous for their GPL-A antigens and serologically characterized outbreds, it has been possible to show that antigens of the I region probably play a higher role in NLT reactions. No NLT reactions occur among outbred animals of a closed colony which have been bred to homozygozity for their GPL-A antigens and thereby probably possess haplotype homozygozity for their major histocompatibility complex. The NLT reaction among serologically characterized guinea pigs may become a convenient way to detect new specificities and recombinant progeny.

Animals↗

Intramural nerve-mediated inotropic responses of left atria of rats and guinea pigs: demonstration of alpha adrenergic and nonadrenergic noncholinergic responses in guinea pigs.

The effects of transmural nerve stimulation (TNS) on contractile responses of rat and guinea pig atria were analyzed pharmacologically. Isolated left atria were electrically driven through AgAgCl field electrodes and TNS was performed by brief introduction of defined stimulation patterns through the same electrodes. Step elevations in stimulating voltage induced biphasic inotropic responses in the left atria of both species: an initial negative component which was usually overwhelmed by a subsequent positive one. The transient negative inotropic response was induced by parasympathetic cholinergic nerve excitation, inasmuch as it was abolished by atropine. In the left atrium of the rat, the TNS-induced positive inotropic response was due exclusively to adrenergic nerve excitation through activation of beta-1 adrenoceptors. In contrast, analysis of the time course of responses in guinea pig left atria after nerve stimulation at 10 Hz revealed a positive inotropic response consisting of two phases; rapid and delayed phases were superimposed upon each other. The rapid phase was reduced by atenolol, a beta-1 antagonist, and attenuated further by prazosin, an alpha-1 antagonist. In the presence of both atenolol and prazosin, TNS of guinea pig left atria still induced a positive inotropic response but it had a slow onset and decay. This is termed the delayed phase response. TNS induced a similar delayed inotropic response in atria from surgically sympathectomized or reserpine-pretreated guinea pigs, from which catecholamine-fluorescence nerves and responses to tyramine were absent. These results demonstrate that TNS excitated adrenergic, cholinergic and nonadrenergic noncholinergic nerves in guinea pig left atria.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylcholine↗