Pentylenetetrazole-induced parasympathetic blood flow increase in the lower lip of the cat

The pentylenetetrazole (30 mg/kg i.v.)-induced blood flow increase in cat lip was more marked on the sympathectomized side than on the intact side (P < 0.01). This difference is probably dependent on the degree of simultaneous activation of the sympathetic nerve elicited by pentylenetetrazole administration. The blood flow increases were markedly suppressed by prior treatment with hexamethonium (10 mg/kg i.v.), an autonomic ganglion blocker (P < 0.01). Combined section of the facial and glossopharyngeal nerve roots completely abolished the blood flow increases elicited by pentylenetetrazole administration (P < 0.01), but section of either the facial or glossopharyngeal nerve root alone failed to produce complete abolition (P < 0.05). These results indicate that the relevant parasympathetic vasodilator fibers originate not only from the glossopharyngeal, but also the facial nerves and that both participate in pentylenetetrazole-induced vasodilatation in the cat lower lip.

Effect of baseline vascular tone on vasomotor responses in cat lip

1. Parasympathetic vasodilator and sympathetic vasoconstrictor responses were monitored using laser Doppler measurement of red cell flux in the lips of anaesthetized and artificially ventilated cats. 2. Three relationships were investigated: (i) that between the reflex parasympathetic vasodilator response induced by lingual nerve (LN) stimulation and baseline red cell flux (BRCF) levels adjusted by repetitive stimulation of the cervical sympathetic nerve (CSN) at various frequencies; (ii) that between the sympathetic vasoconstrictor response elicited by CSN stimulation and the adjusted BRCF levels; and (iii) that between the vasomotor response evoked by simultaneous stimulation of the LN and CSN and the adjusted BRCF levels. 3. The amplitude of the parasympathetic vasodilator response increased as BRCF decreased. In contrast, the amplitude of the sympathetic vasoconstrictor response increased in line with BRCF. 4. Simultaneous activation of the parasympathetic and sympathetic nerves induced a blood flow decrease at high BRCF levels but an increase at low levels. 5. The tendency for the skin of cold subjects to vasodilate and that of warm ones to vasoconstrict in response to various types of stimuli discussed in the light of the present findings.

Bipolar hip arthroplasty without acetabular bone-grafting for dysplastic osteoarthritis. Results after 6-9 years

The authors report the clinical and radiographic results of 36 bipolar hip arthroplasties after performing excavation of the steep and shallow acetabulum without acetabular bone-grafting for dysplastic osteoarthritis. The procedures were carried out between 1981 and 1985. Survivorship analysis showed that 84.6 of the bipolar hip arthroplasties were retained for 8 years. Twenty-nine patients, which were followed for 6-9 years after surgery, were reviewed. Severity of acetabular dysplasia was classified according to the method of Crowe. Class 1 included 17 hips and class 2 included 12 hips. The average preoperative clinical score was 49 points. The average postoperative clinical hip score improved to 87 points after 6 years. Twenty-seven of the 29 hips assessed were classified as either excellent or good by Charnley's function score. Stress fracture, due to excessive acetabular excavation at the time of surgery, and femoral component loosening were major symptomatic complications. The cessation of radiographic evidence of migration of the bipolar socket was recognized in 25 of 29 procedures at 6 years after surgery (86.2%). Cineradiographic study demonstrated that the abduction motion under standing position for 20 of 24 hip joints functioned dominantly at the inner-bearing and metallic-stem interface.

[Effect of dexamethasone on intercellular adhesion molecule-1 expression on cultured bronchial epithelial cells stimulated by inflammatory cytokines]

Bronchial asthma is characterized as a chronic inflammation of the airway that causes an infiltration of lymphocytes and eosinophils. Cell to cell interaction or cell to tissue interaction is essential for infiltration of eosinophils to underlying tissues. These phenomena are closely related to the expression of intercellular adhesion molecule-1 (ICAM-1). Inhalation of steroids, such as beclomethasone dipropionate, is commonly used to cure airway inflammation. In this study, we investigated the effect of cytokines on ICAM-1 expression on human bronchial epithelial cell lines, NCI-H292. Moreover, the effect of dexamethasone on ICAM-1 expression stimulated by IL-1 beta, TNF-alpha and IFN-gamma was observed. Treatment with IL-1 beta, TNF-alpha and IFN-gamma dose-dependently increased ICAM-1 expression on NCI-H292 cells. Inhibitory effects were exerted by dexamethasone on ICAM-1 expression in cells stimulated by IL-1 beta and IFN-gamma in a dose-dependent manner, but not in cells stimulated by TNF-alpha. These results suggest that the inhibition of ICAM-1 expression could be related to the pharmacological action of steroid drugs.

Effect of Kil769, a novel K(+)-channel opener, on sensitivity to Ca2+ of contractile elements and inositol phosphate formation in porcine coronary artery

To determine whether Kil769, a novel K(+)-channel opener, acts intracellularly in vasorelaxation, we compared the effects of Kil769 on force of contraction, intracellular Ca2+ concentration ([Ca2+]i) and inositol phosphate (IP1) formation with those of Ca(2+)-channel blockers in isolated porcine coronary artery. Kil769 (10 microM) and verapamil (1 microM), which produced submaximal relaxation, reduced the increase in [Ca2+]i and force of contraction induced by 25 mM KCl. Verapamil reduced [Ca2+]i and the force of contraction to a similar extent but Kil769 reduced force of contraction more strongly than it did [Ca2+]i. Kil769 also inhibited U46619 (9,11-dideoxy-9 alpha,11 alpha-methano-epoxy-PGF2 alpha)-induced IP1 formation and glibenclamide blocked its inhibitory effect. These results suggest that the opening of K+ channels induced by Kil769 reduces the Ca2+ sensitivity of contractile elements and inositol phospholipid hydrolysis which is related to the Ca2+ release from intracellular storage.

[Effects of fluconazole on onychomycosis in the patients with collagen diseases]

Thirty-four patients with collagen diseases suffering from onychomycosis were treated with fluconazole and showed remarkable improvement. Thirty-one patients showed improvement while only four patients showed adverse reactions. More than half of the cases with onychomycosis in their fingers showed improvement within four weeks and complete recovery within 20 weeks after the administration of fluconazole. Patients with collagen diseases are liable to have onychomycosis as an opportunistic infection which is recalcitrant and resistant disease from the previous therapy. In this trial it became obvious that fluconazole was not only effective on onychomycosis but also a safe drug for the patients with collagen diseases.

Salivary secretion in cat submandibular gland mediated by chorda tympani afferents

The aim of the present study was to investigate whether the afferent traffic from the tongue mediated only via the chorda tympani nerve (CTN) can still elicit reflex salivary and vasodilator responses in the cat submandibular gland (SMG) after section of the lingual nerve proper (LNP). Electrical stimulation of the chorda lingual nerve (CLN) at a site approximately 5 mm distal to the intersection of the CLN and the SMG duct elicited salivary and vasodilator responses in the SMG in sympathectomized cats. Both responses were unaffected by section of the LNP. The optimal frequency of CLN stimulation for submandibular salivation and vasodilation was 20 Hz, regardless of whether the LNP had been cut. Prior treatment with the autonomic ganglion blocker hexamethonium (10 mg/kg iv) virtually abolished the salivation and the blood flow increase in SMG. Prior treatment with scopolamine (0.1 mg/kg iv) almost abolished the salivary secretions but had no effect on the vasodilator responses in the SMG elicited by CLN stimulation after LNP section. The mechanism underlying the reflex submandibular salivation mediated by chorda tympani afferents appears to involve parasympathetic muscarinic receptors, but the mechanism for the vasodilator response has yet to be established. These results indicate that afferent traffic passing through the CTN on CLN stimulation is importantly involved in the parasympathetic reflex secretory and vasodilator responses in the cat SMG.

Two types of vasodilatation in cat choroid elicited by electrical stimulation of the short ciliary nerve

Choroidal blood vessels are innervated by three types of vasoactive nerve fibers: sympathetic, parasympathetic and sensory fibers in the short ciliary nerve. We investigated whether or not stimulation of the short ciliary nerve elicits vasodilatation. In 30 cats (2-4 kg) anesthetized with pentobarbital sodium (30 mg kg-1, i.v.) and artificially ventilated (pancuronium bromide; 0.2 mg kg-1 hr-1, i.v.), choroidal blood flow was continuously measured trans-sclerally with a laser Doppler flowmeter. The lateral short ciliary nerve was stimulated electrically (0-50 V, 2 msec, 20 Hz, for 10 sec) at two sites, one close to the eyeball (site P) and the other between the main and accessory ciliary ganglia (site Q). Choroidal vasodilatation occurred with a high incidence (80%) in response to electrical stimulation of the short ciliary nerve at site P or Q, when cats had been treated with the alpha-adrenergic blocking agent phentolamine (3 mg kg-1) to eliminate sympathetic vasoconstrictor effects. A long-lasting vasodilatation was observed during 1% capsaicin application to the nerve bundle at site P, but not at site Q and capsaicin nearly abolished the vasodilatation evoked by stimulation at site P, but not that evoked from site Q. Vasodilatation elicited by electrical stimulation at site P or Q was not sensitive to the ganglion-blocking agent hexamethonium (3 mg kg-1, i.v.).(ABSTRACT TRUNCATED AT 250 WORDS)

Increased and decreased choroidal blood flow elicited by cervical sympathetic nerve stimulation in the cat

The effect of electrical stimulation of the cervical sympathetic nerve on choroidal blood flow in the cat was investigated. Flow at various sites in 30 pentobarbital-anesthetized cats was continuously measured trans-sclerally using a laser Doppler flowmeter. Changes in either direction, increases and decreases, occurred in response to electrical stimulation of the peripheral cut end of the cervical sympathetic nerve. These changes in flow appeared to depend on the site of choroidal blood flow measurement, as decreases were seen at sites with a high baseline blood flow and increases at sites with a low baseline level. Both types of response were reduced when the cats were treated with the alpha-adrenoreceptor antagonist phentolamine, but not by treatment with the beta-adrenoceptor antagonist propranolol. The decrease in choroidal blood flow elicited by cervical sympathetic nerve stimulation appears to be mediated via the vasoconstrictor fibers in that nerve. A choroidal blood flow increase may occur as a secondary effect following vasoconstriction of the arterioles elicited by cervical sympathetic nerve stimulation, producing a passive net increase in choroidal blood flow.

Parasympathetic reflex salivary secretion in the cat parotid gland

The aim of the present study was to compare and to characterize the secretory and vasodilator effects in the parotid gland of sympathectomized cats elicited reflexly by electrical stimulation of the central cut ends of the chorda tympani (or glossopharyngeal) nerves (physiologically conveying gustatory stimuli), vagus nerve (visceral stimuli), and the lingual nerve after cutting the chorda tympani nerve (somatic stimuli). The threshold stimulus-intensity needed to elicit the salivary secretion and a blood flow increase was markedly lower for stimulation of the chorda tympani nerve and glossopharyngeal nerve (2 V for each nerve) than for the lingual nerve, inferior alveolar nerve, and vagus nerve (10 V for each nerve). The salivary and vasodilator responses to stimulation of each afferent nerve were all abolished by prior treatment with hexamethonium at a dose of 5 mg/kg, i.v. Prior treatment with scopolamine completely abolished the salivary secretion elicited by lingual nerve and glossopharyngeal nerve stimulation, but had less effect on the vasodilator response in the parotid gland. These results indicate that the secretory and vasodilator responses evoked by afferent traffic in the above nerves are mediated via an activation of the autonomic nervous system, particularly by a parasympathetic mechanism. They suggest that there is a marked difference in the ability of different sensory modalities to induce reflex salivary secretion and vasodilatation, there being low threshold nerve fibers in the chorda tympani and glossopharyngeal nerves and high threshold nerve fibers in the lingual nerve, vagus nerve, and inferior alveolar nerve.

Stimulation of interleukin-6 production of periodontal ligament cells by Porphyromonas endodontalis lipopolysaccharide

Interleukin-6 (IL-6), which is a multifunctional cytokine, has important roles in acute and chronic inflammation and may also be implicated in bone resorption. We examined the IL-6 production in periodontal ligament (PDL) cells which were treated with lipopolysaccharide (LPS) from several oral inflammatory pathogens. The LPS from Porphyromonas endodontalis, which was isolated from infected root canals and radicular cyst fluids, was more potent than the LPS from any other periodontal organisms examined. P. endodontalis LPS stimulated IL-6 release from PDL cells in a time- and dose-dependent manner. Northern blot hybridization analysis revealed that the IL-6 mRNA level in PDL cells was increased by P. endodontalis LPS. These results suggest that stimulation of the IL-6 release of PDL cells by P. endodontalis LPS may have a role in the progression of inflammation and alveolar bone resorption in periodontal and periapical diseases.

Axon reflex vasodilatation in cat dental pulp elicited by noxious stimulation of the gingiva

Antidromic stimulation of sensory nerves has been shown to increase blood flow in the tissue they innervate. This study was designed to determine if antidromic vasomotor responses occur in feline dental pulp and if they are mediated by branched axons supplying both tooth pulp and gingiva. Dynamic changes in pulpal blood flow (PBF) elicited by electrical stimulation, pinching, heating, and capsaicin application to the gingivae were investigated in cat mandibular canine teeth by means of Laser Doppler Velocimetry. All inferior alveolar nerve bundles and the cervical sympathetic trunk had been previously sectioned to avoid the occurrence of brainstem reflexes, e.g., somato-autonomic vasomotor reflexes. Increases in PBF were observed in seven out of 12 cats when a restricted gingival area adjacent to the canine teeth was stimulated as described, but the increases were abolished after the sensitive gingival area was painted with lidocaine jelly, a surface anesthetic. These vasodilator responses, remarkably reduced following repeated application of 30 mM of capsaicin, are considered to be induced via antidromic activation of capsaicin-sensitive nociceptive nerve fibers, presumably by axon reflex mechanisms, suggesting that nerve terminals supplying the gingiva originate from parent axons which have collaterals that innervate the canine tooth pulp.

[A resected case of esophageal leiomyoma with 15 cm in long diameter, diagnosed by transesophageal ultrasonic endoscopy]

A 28-year-old man whose chest X-ray film showed a mass on the right upper mediastinum was admitted. Preoperative examination, including CT, MRI, esophagogram, did not make it possible to determine clinically from which organ the tumor originated. On diagnosing with transesophageal ultrasonic endoscopy (TUE) the tumor was found to originate in the esophageal submucosa, with no involvement of the mediastinal organ apparent. Esophageal sub-mucosal tumor enucleation was performed. The resected tumor was 15 cm in long diameter and weighed 125 g. We therefore believe that TUE is clinically useful in diagnosing the tumor originating in the esophageal wall or adjoining esophageal wall.

[Moabit Hospital in Ogai Mori's "Diary in Germany" and its history]

On August 17th, 1887, Dr. Ogai Mori and Dr. Tadanori Ishiguro visited Moabit Hospital (City Hospital of Berlin at Moabit), where later in April, 1891, Dr. Jiro Tuboi learned tuberculin therapy for tuberculosis from Dr. Robert Koch. The history of this hospital is reviewed. In a severe epidemic of smallpox in 1870 to 1871, the City of Berlin provided four temporary institutions to admit the patients, but one of them, borrowed from a field hospital in Tempelhof, had to be removed because of a claim from the military bureau. As a substitute, barracks and accessories were built in the Moabit district in 1872. In the later half of the 19th century, medical demand in Berlin was markedly increased by rapid expansion of population. To meet this demand, following the institution opened in Friedlichshain in 1874, the barracks in Moabit became a city hospital for Berlin citizens in 1875. From 1920, the hospital was affiliated with the University of Berlin. Having overcome difficulties under the National-Socialistic rule, World War II, and the plight in international politics after the war, the hospital serves now, as much as in the past, the citizens of Berlin.

Inhibition of tubular morphogenesis in human microvascular endothelial cells by co-culture with chondrocytes and involvement of transforming growth factor beta: a model for avascularity in human cartilage

Tube formation in collagen gel was induced in human omental microvascular endothelial (HOME) cells in the presence of epidermal growth factor (EGF) or transforming growth factor-alpha (TGF-alpha). TGF-alpha enhanced the expression of the tissue type plasminogen activator (t-PA) gene, whereas TGF-beta increased the expression of the PA inhibitor-1 (PAI-1) gene and inhibited that of the t-PA gene. TGF-beta inhibited the tube formation of HOME cells in type I collagen gel that was enhanced in response to TGF-alpha. We have recently established an angiogenesis model in vitro in which vascular endothelial cells on type I collagen gel in an inner chamber are co-cultured with other types of cells in an outer chamber. Here we examined whether the EGF/TGF-alpha-induced tube formation in HOME cells was modulated by human chondrocytes co-culture in the outer chamber. TGF-alpha-dependent tube formation of HOME cells was inhibited when human chondrocytes were co-cultured in the outer chamber. This chondrocyte-induced inhibition of tube formation was partly abrogated by co-administration of anti-TGF-beta antibody. These findings suggest that TGF-beta is partly involved in the human chondrocyte-dependent inhibition of tube formation by human microvascular endothelial cells. This is the first model system demonstrating that avascularity of human chondrocytes is partly due to TGF-beta family produced from them.

[Experimental research on choroidal circulation. 2. Choroidal blood flow increase elicited by electrical stimulation of parasympathetic nerve behind the eyeball in the cat]

The present studies were performed to examine whether the nerves behind the eye ball contain parasympathetic fibers which dilate the choroidal blood vessels. Choroidal blood flow in the cat (20 animals) was measured trans-sclerally with a laser Doppler flowmeter. Cats were anesthetized with pentobarbital sodium (30 mg/kg, i.v.) and artificially respirated after injection of pancuronium bromide (0.2 mg/kg/hr, i.v.). Electrical stimulation of the short ciliary nerve as well as of the nerve between the ciliary ganglion and accessory ciliary ganglion, where the sensory nerve is absent, elicited an increase choroidal blood flow in an intensity-dependent manner. Application of capsaicin, which is known to desensitize the polymodal nociceptive C-fibers, to these nerves did not abolish the increase in blood flow in response to electrical stimulation of the short ciliary nerve. Atropine, a muscarinic receptor antagonist, and phentolamine, an alpha-adrenoceptor blocking agent, had no effect on these responses. The results suggest that the blood flow increase elicited by stimulation of these nerves is mediated via activation of the atropine-resistant parasympathetic vasodilator fibers supplying the choroid in the cat.

Salt preference elicited by chronic intracerebroventricular angiotensin II

1. Much more water was consumed than either 0.9% or 2.7% saline in response to various dipsogenic stimuli in untreated normal replete rats when they had free access to water, 0.9% and 2.7% saline. On the other hand, the rats drank more 0.9% saline than water and 2.7% saline when each solution is the sole drinking fluid offered. 2. A marked increase in preference for 0.9% saline was observed during the chronic i.c.v. injection of angiotensin II at a dose of 25 ng/hr for 7 consecutive days in the three bottle choice test. After the cessation of angiotensin II infusion, most rats (45 out of 50 rats) returned to drink much more water than 0.9% and 2.7% saline, similar to the drinking pattern of the 0.9% saline-treated control rats. However, some rats (5 out of 50 rats) still preferred 0.9% saline and this persisted for up to 3 months although these rats did not show a hypertensive state and an increase of plasma renin activity.

Vasospasmolytic effect of KRN2391 on 3,4-diaminopyridine-induced rhythmic contraction of porcine coronary artery

1. In the present study, we examined the vasospasmolytic effect of KRN2391 on rhythmic contractions of porcine coronary artery caused by 3,4-diaminopyridine (3,4-DAP) compared with cromakalim and nitroglycerin. 2. KRN2391 at 10(-7) showed a tendency to prolong the cycle length and at 10(-6) M completely eliminated rhythmic contractions in all preparations. The elimination by 10(-6) M KRN2391 was antagonized by either oxyhemoglobin (10(-5) M) or glibenclamide (3 x 10(-6)) although not completely. 3. Cromakalim at 10(-5) M and nitroglycerin at 10(-7) M completely eliminated 3,4-DAP-induced rythmic contractions in all preparations. The elimination by cromakalim and nitroglycerin was completely antagonized by glibenclamide and oxyhemoglobin, respectively. 4. The present study suggests that the vasospasmolytic effect of KRN2391 on 3,4-DAP-induced rhythmic contractions is based on its nitrate action and K channel opening action.

[Effect of sevoflurane on blood flow velocity in the vertebral artery]

Blood flow velocity in the vertebral artery was measured using transcranial Doppler sonography during sevoflurane anesthesia in 12 patients in the knee-chest position. The correlation between mean arterial blood pressure (MBP) and mean blood flow velocity in the vertebral artery (Vmean) was significant in each patient. Normalized data expressed as a percentage of the individual arithmetic means permitted a composite analysis of data from all patients. Linear regression of normalized MBP (%MBP) on normalized Vmean (%Vmean) showed %Vmean = 24.8 +/- 0.75 %MBP (r = 0.78, P < 0.01). The results of the present study suggest that fluctuations in systemic blood pressure may lead to fluctuations in cerebral blood flow. Therefore, the use of sevoflurane anesthesia must be accompanied by careful management of blood pressure during surgery.

Cross talk of tumor necrosis factor-alpha and epidermal growth factor in human microvascular endothelial cells

Our previous studies imply that tumor necrosis factor-alpha (TNF-alpha) and epidermal growth factor (EGF) might share a common signal transduction pathway in human omental microvascular endothelial (HOME) cells. Exposure of cultured HOME cells to TNF-alpha for 10 min enhanced EGF receptor phosphorylation at a rate comparable to EGF. Apparent phosphorylation of tyrosine residues was observed in addition to serine/threonine of the EGF receptor by EGF, but only a slightly if any tyrosine phosphorylation by TNF-alpha. In vitro kinase activity of EGF receptor was also enhanced by TNF-alpha as well as by EGF. Furthermore, expression of the c-fos gene was enhanced in response to either EGF or TNF-alpha. Pretreatment of HOME cells with EGF for 12 h almost completely blocked the induction of the c-fos gene by EGF and partially blocked the c-fos induction by TNF-alpha. TNF-alpha-induced c-fos gene expression appeared to be partly due to its transactivation of EGF receptor. EGF and TNF-alpha could enhance c-fos gene expression when protein kinase C was down-regulated by phorbol ester myristate (PMA). Gel retardation assay with the NF-kappa B consensus sequence showed that NF-kappa B binding activity was dramatically activated by TNF-alpha, but not by EGF or PMA. The binding of another transcription factor, AP-1 (Jun/Fos), was enhanced by EGF, TNF-alpha, and PMA, whereas TNF-alpha could still activate AP-1 after longer exposure to EGF. TNF-alpha-induced activation of c-fos gene appears to be mediated through pleiotropic mechanisms and partly through a common signal with EGF, possibly through EGF receptor in microvascular endothelial cells.

Cardiovascular effects of KRN2391, nitroglycerin and cromakalim in dihydroergotamine-treated pithed rats

1. The effects of KRN2391 on the cardiovascular system were compared with those of nitroglycerin and cromakalim in pithed rats treated with dihydroergotamine (DHE) in order to examine the effects of these drugs on venous blood vessels. 2. DHE (100 micrograms/kg, i.v.) produced increases in mean blood pressure (MBP), cardiac output (CO) and central venous pressure (CVP) without changes in total peripheral vascular resistance (TPR) and heart rate (HR) based on venoconstriction. The DHE-treated pithed rats, nitroglycerin (30 micrograms/kg, i.v.) decreased CO and CVP whereas cromakalim (30 micrograms/kg, i.v.) produced a slight increase in CO followed by a decrease and did not affect CVP. KRN2391 (30 micrograms/kg, i.v.) produced a decrease in CVP without affecting CO. Decreases in MBP and TPR were induced by all drugs. 3. These results suggest that nitroglycerin acts predominantly as a venodilator and KRN2391 and cromakalim showed a venodilating action in addition to an arterial dilating action in DHE treated pithed rats. However, the venodilating action of KRN2391 in this condition is more potent than that of cromakalim.

Experimental combination chemotherapy of pirarubicin with various antitumor drugs against P388 murine leukemia

We have examined the therapeutic effects of combination therapy of pirarubicin ((2"R)-4'-O-tetrahydropyranyladriamycin, THP) with various antitumor agents against P388 murine leukemia. THP showed a high antitumor activity in combination with various antitumor drugs, especially with cyclophosphamide (CPM), cisplatin (CDDP), mitomycin C (MMC), enocitabine (BHAC), vindesine (VDS) or methotrexate (MTX). The effects of combination therapy depended on the order of administration of THP and combined drugs. THP-preceding treatment gave more synergistic effects in combination with 5-fluorouracil (5-FU) or MTX. THP-preceding or simultaneous treatment with etoposide (ETP) indicated the higher synergistic activity than ETP-preceding one. Moreover, THP showed much higher synergistic effects in any order of the combination with CPM, CDDP, MMC, BHAC, VDS or MTX. These results suggest that THP possesses a therapeutic usefulness clinically in combination with various antitumor drugs, if the selection of drugs combined with THP and the order of administration are suitable.

Parasympathetic-mediated reflex salivation and vasodilatation in the cat submandibular gland

The aim of the present study was to compare and characterize the secretory and vasodilator effects induced by chorda lingual nerve (CLN) stimulation (i.e., direct parasympathetic stimulation) and reflex parasympathetic stimulation in the submandibular gland (SMG) of sympathectomized cats. The increase in blood flow and salivary secretion in response to electrical stimulation of the central cut ends of the vagus and inferior alveolar nerves, as well as to stimulation of the CLN at a site approximately 5 mm distal to the intersection of the CLN and the SMG duct (site D) was completely abolished by section of the chorda tympani nerve (CTN). Neither response to CLN stimulation at a site nearly 5 mm proximal to the intersection of the CLN and the SMG duct (site C) was affected by CTN section. Section of the CLN at a site approximately 5 mm distal to the intersection of the CTN and the CLN abolished the submandibular salivary and vasodilator responses elicited by CLN stimulation at site D but had no effect on the two responses evoked by CLN stimulation at site C. The blood flow increases evoked by electrical stimulation of the CLN at site D were greatly reduced by prior treatment with the autonomic ganglion blocker hexamethonium, but the vasodilator responses evoked from site C were reduced much less. These data suggest that the secretory and vasodilator responses elicited by CLN stimulation at site D and those by vagus and inferior alveolar nerve stimulation are mediated largely via a parasympathetic reflex mechanism.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparative analysis of vasodilating mechanisms of Ki1769, Ki3315 and KRN2391, pyridinecarboximidamide derivatives, in porcine isolated coronary artery

1. The vasodilating mechanisms of pyridinecarboximidamide derivatives which have a nitroxyl group (KRN2391), a phenyl group (Ki1769) or a hydroxyl group (Ki3315) were studied in porcine isolated coronary artery. 2. KRN2391 (10(-6) M) increased cyclic GMP formation but did not affect intracellular cyclic AMP level. Ki1769 (10(-5) M) and Ki3315 (10(-3) M) had no effect on intracellular cyclic GMP and cyclic AMP levels. 3. Despite producing submaximal relaxation at KRN2391 (10(-6) M) and nitroglycerin (10(-6) M), the increase in cyclic GMP caused by KRN2391 was lower than that caused by nitroglycerin. 4. Methylene blue (10(-5) M) inhibited KRN2391- and nitroglycerin-induced relaxations but did not affect Ki1769- and Ki3315-induced relaxation. 5. Glibenclamide (10(-6) M) inhibited KRN2391-, Ki1769- and Ki3315-induced relaxation but did not affect nitroglycerin-induced relaxation. 6. These results suggest that the nitroxyl group of KRN239 contributes to its nitrate action and the pyridinecarboximidamide moiety plays an important role of developing a K channel opening action.