Carbon Monoxide ; physiology ; Humans ; Nervous System Diseases ; physiopathology ; Neurotransmitter Agents ; physiology ; Nitric Oxide ; physiology

AIM AND METHODSTo study the roles of carbon monoxide on hypoxic pulmonary vasoconstriction (HPV) by investigating the effects of exogenous carbon monoxide and heme oxygenase inhibitor ZnPPIX on hypoxic vasoconstriction reaction of isolated rat pulmonary arterial rings (PAR).

RESULTSHypoxia caused constriction in PAR preconstricted by PE. Both ZnPPIX and carbon monoxide inhibited hypoxic pulmonary constriction significantly by increasing the cGMP level after hypoxia.

CONCLUSIONZnPPIX and exogenous carbon monoxide can inhibit HPV. The reduction of cGMP induced by the decreased of CO may be one of reasons of HPV.

Animals ; Carbon Monoxide ; physiology ; Hypoxia ; In Vitro Techniques ; Male ; Pulmonary Artery ; physiology ; Rats ; Rats, Wistar ; Vasoconstriction ; physiology

This study was performed to observe the changes of blood sugar levels in 200 cases with acute Carbon monoxide (CO) poisoning. Successive tests of blood sugar on the day of onset and the lst, 2nd, 3rd & 4th day after anoxic insult were done in 12 patients with acute CO poisoning. In addition, to determine the derangement of thyroid function, blood levels of triiodothyronine(T3), tetraiodothyronine(T4), thyroid-stimulating hormone (TSH) were measured on the day of admission in 29 with C0 poisoning. The blood levels of T3, T4 and TSH were within normal ranges, but over two-thirds were distributed in lower range of normal mean values. This lower tendency within normal range was especially prominent in the blood level of T3. The blood level of sugar was increased, and 79.5% was higher than the upper limit of normal range. The blood levels of T3 and T4 were significantly decreased as CO exposure time period- prolonged. There was significant negative correlation between blood T3 levels and consciousness levels. Blood TSH levels were not significantly affected in acute CO poisoning. As consciousness levels were depressed and exposure time period were prolonged, blood sugar was increased. There found a rapid increase in blood sugar, followed by a abrupt dropping, and then progressive decrease to normal level over a period of 5 days after exposure to CO. In conclusion, acute CO poisoning obviously changes the thyroidal physiology. Even though blood TSH levels were variable, there was an obvious decrease in T3. The assumed CO-induced decrease in thyroid hormone secretion is seemingly not mediated by depressed TSH secretion but thyroid hormone metabolic dysfunction or extrathyroidal cotiverslon defect The alterations of blood sugar were also found to be acute and temporal which may be the result of physiologic compensation to hypoxic state caused by CO poisoning.
Blood Glucose ; Carbon Monoxide Poisoning* ; Carbon Monoxide* ; Carbon* ; Compensation and Redress ; Consciousness ; Humans ; Physiology ; Poisoning ; Reference Values ; Thyroid Gland* ; Thyroid Hormones* ; Thyrotropin

Animals ; Carbon Monoxide ; physiology ; Humans ; Hydrogen Sulfide ; toxicity ; Hypertension, Pulmonary ; etiology ; Hypoxia ; complications ; Nitric Oxide ; physiology

Animals ; Animals, Newborn ; Carbon Monoxide ; metabolism ; Heme Oxygenase (Decyclizing) ; metabolism ; Lung ; metabolism ; Oxygen ; physiology ; Rats

OBJECTIVETo study the effect of endogenous carbon monoxide (CO) on the smooth muscle function of the dog penile corpus cavernosum in vitro.

METHODSTissue bioassay was used to measure the corpus cavernosum muscle contraction and relaxation. The production of CO was induced in the corpus cavernosum smooth muscle, and the effect of CO on the penile corpus cavernosum smooth muscle pre-contracted by phenylephrine (PE) was determined.

RESULTSChlorinous hemoglobin could relax the smooth muscle stripes pre-contracted by 10 micromol/L PE. A dose-dependent relaxation was observed. The relaxation responses by 10 -100 micromol/L chlorinous hemoglobin were significant compared with the control group (P < 0. 01). The pretreatment of the muscle stripes with ZnPP-IX or methylthioninium significantly reduced the relaxing effect of chlorinous hemoglobin (P < 0.01).

CONCLUSIONThe relaxing effect of endogenous CO on the smooth muscle of the penile corpus cavernosum depends on the concentration of endogenous CO. The underlying mechanism may involve the pathway from CO to cGMP production.

Animals ; Carbon Monoxide ; physiology ; Dogs ; Dose-Response Relationship, Drug ; Hemin ; pharmacology ; In Vitro Techniques ; Male ; Muscle, Smooth ; drug effects ; physiology ; Penile Erection ; drug effects ; physiology ; Penis ; drug effects ; physiology

OBJECTIVETo explore the relationship of aging with the changes of endogenous carbon monoxide (CO), cGMP and cAMP contents in the penile tissues of rats.

METHODSTwenty-four male rats were equally divided into an 8-month, a 16-month and a 24-month group, and their penile erection was detected by injecting apomorphine, their penile cavernous body harvested, and the contents of CO, cAPM and cGMP detected by improved dual wavelength spectrophotometry.

RESULTSThe contents of CO, cAPM and cGMP were reduced with the increase of age, with statistically significant differences between the three age groups (P < 0.01).

CONCLUSIONAging significantly decreased the contents of CO, cAMP and cGMP in the penile tissues of the rats, which suggests that aging might play an important role in erectile dysfunction.

Aging ; physiology ; Animals ; Carbon Monoxide ; metabolism ; Cyclic AMP ; metabolism ; Cyclic GMP ; metabolism ; Male ; Penis ; metabolism ; Rats ; Rats, Wistar

OBJECTIVETo investigate the protective effect of high-pressure carbon monoxide for preservation of ex vivo rabbit heart graft in comparison with the conventional HTK cardioplegic solution preservation.

METHODSHeart grafts isolated from 85 New Zealand rabbits were randomly divided into Naive group (n=5), HTK group (n=40) and CO group (n=40). The grafts underwent no preservation procedures in Naive group, preserved at 4 degrees celsius; in HTK cardioplegic solution in HTK group, and preserved at 4 degrees celsius; in a high-pressure tank (PO2: PCO=3200 hPa: 800 hPa) in CO group with Krebs-Henseleit solution perfusion but without cardioplegic solution. After preservation for 2, 4, 6, 8, 10, 14, 18, and 24 h, 5 grafts from the two preservation groups were perfused for 30 min with a modified Langendorff apparatus and examined for left ventricular systolic pressure (LVSP), left ventricular diastolic pressure (LVDP), arrhythmia score (AS), myocardial ultrestructure, and cardiac enzyme profiles.

RESULTSAfter preservation for 6 to 24 h, the cardiac enzyme profiles and systolic and diastolic functions were significantly better in CO group than in HTK group, but these differences were not obvious between the two groups after graft preservation for 2 to 4 h. Significant changes in the myocardial ultrastructures occurred in the isolated hearts after a 24-h preservation in both CO and HTK groups, but the myocardial damages were milder in CO group.

CONCLUSIONPreservation using high-pressure carbon monoxide can better protect isolated rabbit heart graft than the conventional HTK preservation approach especially for prolonged graft preservation.

Animals ; Carbon Monoxide ; Cardioplegic Solutions ; Glucose ; Heart ; physiology ; Heart Transplantation ; Myocardium ; ultrastructure ; Rabbits ; Tissue Preservation ; methods ; Tromethamine

OBJECTIVETo explore the relationship between plasma levels of carbon monoxide and blood-brain permeability in cirrhotic rats.

METHODSWe measured mean arterial pressure (MAP), heart rate, plasma levels of carbon monoxide and amount of Evans blue in the brain tissue taken as the index of blood-brain permeability in cirrhotic rats (n=10) and controls (n=10).

RESULTSCirrhotic rats showed significant increases in plasma carbon monoxide and amount of Evans blue in brain tissue compared with controls [(18.37 +/- 1.79) micromol/L,(18.52 +.- 1.39) ng/mg vs (10.27 +/- 1.21) micromol/L, (15.08 +/- 1.06) ng/mg; P< 0.01]. Carbon monoxide levels in cirrhotic rats correlated positively with blood-brain barrier permeability and inversely with MAP (r=0.72, P< 0.01; r= -0.67, P< 0.05).

CONCLUSIONSCarbon monoxide, involving in the occurrence of hypotension and the increase of blood-brain barrier permeability, may play a role in the development of hepatic encephalopathy.

Alanine Transaminase ; blood ; Animals ; Aspartate Aminotransferases ; blood ; Blood Pressure ; physiology ; Blood-Brain Barrier ; physiology ; Capillary Permeability ; physiology ; Carbon Monoxide ; blood ; Carbon Tetrachloride ; Heart Rate ; physiology ; Liver Cirrhosis, Experimental ; blood ; chemically induced ; physiopathology ; Male ; Rats ; Rats, Sprague-Dawley ; gamma-Glutamyltransferase ; blood

The aim of the present study was to investigate the effect of endogenous carbon monoxide (CO) on respiratory rhythm. The experiments were carried out on the medullary slices of newborn Sprague-Dawley rats. The rhythmic discharge frequency (DF) of hypoglossal rootlets was taken as an index of rhythmic respiratory activity. The slices of medulla oblongata were superfused with ZnPP-9 (inhibitor of heme oxygenase), CO and hemin (substrate of heme oxygenase), respectively, to observe their effects on respiratory rhythm. The preparations were divided into 5 groups: control group of artificial cerebrospinal fluid (ACSF), group of ZnPP-9, group of exogenous CO, group of hemin and group of ZnPP-9 + hemin. The results obtained were as follows. In ZnPP-9 group, the rhythmic DF of the hypoglossal rootlets was increased (P<0.05); while in exogenous CO group, it was decreased (P<0.05). In the groups of hemin and ZnPP-9 + hemin, the rhythmic DF of the hypoglossal rootlets was increased (P<0.05). It is suggested that endogenous CO may play an important role in the regulation of respiratory rhythm.
Animals ; Animals, Newborn ; Carbon Monoxide ; physiology ; Female ; Hemin ; pharmacology ; Hypoglossal Nerve ; drug effects ; physiology ; Male ; Protoporphyrins ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Respiration