Cardiovascular and inflammatory response to cholecystokinin during endotoxemic shock.

Cholecystokinin (CCK) was first described as a gastrointestinal hormone, but its receptors have been located in cardiac and vascular tissues, as well as in immune cells. Our aims were to investigate the role of CCK on lipopolysaccharide (LPS)-induced hypotension and its ability to modulate previously reported inflammatory mediators, therefore affecting cardiovascular function. To conduct these experiments, rats had their jugular vein cannulated for drug administration, and also, the femoral artery cannulated for mean arterial pressure (MAP) and heart rate records. Endotoxemia induced by LPS from Escherichia coli (1.5 mg/kg; i.v.) stimulated the release of CCK, a progressive drop in MAP, and increase in heart rate. Plasma tumor necrosis factor α (TNF-α), interleukin 10 (IL-10), nitrate, vasopressin, and lactate levels were elevated in the endotoxemic rats. The pretreatment with proglumide (nonselective CCK antagonist; 30 mg/kg; i.p.) aggravated the hypotension and also increased plasma TNF-α and lactate levels. On the other hand, CCK (0.4 µg/kg; i.v.) administered before LPS significantly restored MAP, reduced aortic and hepatic inducible nitric oxide synthase (iNOS) production, and elevated plasma vasopressin and IL-10 concentrations; it did not affect TNF-α. Physiological CCK concentration reduced nitrite and iNOS synthesis by peritoneal macrophages, possibly through a self-regulatory IL-10-dependent mechanism. Together, these data suggest a new role for the peptide CCK in modulating MAP, possibly controlling the inflammatory response, stimulating the anti-inflammatory cytokine, IL-10, and reducing vascular and macrophage iNOS-derived nitric oxide production. Based on these findings, CCK could be used as an adjuvant therapeutic agent to improve cardiovascular function.

Proglumide enhances the antinociceptive effect of cyclooxygenase inhibitors in diabetic rats in the formalin test.

The purpose of this study was to assess the effect of the non-selective cholecystokinin receptor antagonist proglumide on the antinociceptive activity of ketorolac and meloxicam in non-diabetic and diabetic rats. Streptozotocin (60 mg/kg) injection caused hyperglycemia which was maintained for 2 weeks. Formalin-evoked flinching was increased in diabetic rats as compared to non-diabetic rats. Local peripheral ipsilateral, but not contralateral, administration of ketorolac and meloxicam produced antinociception in non-diabetic and diabetic rats. However, the antinociceptive effect of both drugs was significantly reduced in diabetic animals. Proglumide was ineffective by itself and it did not affect the antinociception induced by the cyclooxygenase inhibitors in non-diabetic rats. Contrariwise, proglumide reduced formalin-induced nociception and it increased ketorolac- or meloxicam-induced antinociception in diabetic rats. These results suggest that peripheral cholecystokinin plays an important role in diabetes-induced sensitization as well as in the reduction of the antinociceptive effects of ketorolac and meloxicam in diabetic rats. The combination of cholecystokinin receptor antagonists and ketorolac or meloxicam may be a useful strategy to reduce nociception in diabetic patients.

Peripheral participation of cholecystokinin in the morphine-induced peripheral antinociceptive effect in non-diabetic and diabetic rats.

The effects of cholecystokinin (CCK-8) and the CCK receptor antagonist proglumide, on antinociception induced by local peripheral (subcutaneous) injected morphine in non-diabetic (ND) and streptozotocin-induced diabetic (D) rats, were examined by means of the formalin test. Morphine induced dose-dependent antinociception both in ND and D rats. However, in D rats, antinociceptive morphine potency was about twofold less than in ND rats. Pre-treatment with CCK-8 abolished the antinociceptive effect of morphine in a dose-dependent manner in both groups of rats. Additionally, proglumide enhanced the antinociceptive effect induced by all doses of morphine tested. Both CCK-8 and proglumide had no effect on flinching behaviour when given alone to ND rats. Unlike ND rats, in D rats proglumide produced dose-dependent antinociception and CCK-8 enhanced formalin-evoked flinches, as observed during the second phase of the test. In conclusion, our data show a decrease in peripheral antinociceptive potency of morphine when diabetes was present. Additionally, peripheral CCK plays an antagonic role to the peripheral antinociceptive effect of morphine, additional to the well known CCK/morphine interaction at spinal and supraspinal level.

Anxiogenic effect of cholecystokinin in the dorsal periaqueductal gray.

Systemic administration of cholecystokinin (CCK) fragments produces anxiogenic effects. The dorsal periaqueductal gray (dPAG) has been related to anxiety and panic reactions. The objective of this study was to investigate a possible anxiogenic effect of CCK-8 microinjected into the dPAG. At 10 min after the last microinjection (0.5 microl) into the dPAG male Wistar rats (N=7-17) were tested in the elevated plus-maze, an animal model of anxiety. The following treatments were tested alone or in combination: sulfated CCK-8 (CCK-8s, 0.5-1 microg), PD 135158 (N-methyl-D-glucamine, 0.1 microg), a CCK-2 receptor antagonist, lorglumide (0.1-0.3 microg), a CCK-1 receptor antagonist. In addition, Fos immunohistochemistry was performed in rats (n=3-4) treated with CCK-8s (1 microg) alone or in combination with PD 135158 (0.1 microg). CCK-8s produced anxiogenic-like effect, decreasing the percentage of time spent in open arm (saline=30.3+/-6.6, CCK 0.5 microg=15.2+/-1.8; CCK 1 microg=14.6+/-2.1). This effect was prevented by pretreatment with PD 135158, but not by lorglumide. CCK-8s injected into the dPAG induced Fos immunoreactivity in several brain areas related to defensive behavior, including the PAG, median, and dorsal raphe nuclei, superior colliculus, lateral septal nuclei, medial hypothalamus, and medial amygdala. This effect was also prevented by pretreatment with PD 135,158. These results suggest that CCK-8s, acting on CCK-2 receptors, may modulate anxiety reactions in the dPAG.

Involvement of local cholecystokinin in the tolerance induced by morphine microinjections into the periaqueductal gray of rats.

The ventrolateral periaqueductal gray (PAG) is a key structure for the development of opioid tolerance. An increased activity of 'anti-opioids' like cholecystokinin (CCK) has been proposed as a possible mechanism for opioid tolerance. The present study evaluates the role of PAG-located CCK in the opioid tolerance induced by repeated microinjections of morphine (MOR) into PAG. Male rats were implanted with chronic guide cannulae aimed at the PAG. Microinjection of MOR (0.5 microg in 0.5 microl) into PAG caused antinociception as quantified with the tail flick and the hot plate tests. When MOR microinjection was repeated twice daily, the antinociceptive effect disappeared within 2 days (tolerance). However, if each MOR microinjection was preceded (within 15 min) by a microinjection of the non-selective CCK receptor antagonist proglumide (PRO), (0.4 microg in 0.5 microl) into the same PAG site, the microinjections of MOR always produced antinociception and did not induce tolerance. If PRO microinjections were suspended, subsequent MOR microinjections induced tolerance. In MOR-tolerant rats, a single PRO microinjection into the same PAG site was enough to restore the antinociceptive effect of MOR. On the other hand, if CCK (1 ng in 0.5 microl) was microinjected into PAG, then MOR microinjection administered 15 min later into the same PAG site did not elicit antinociception. These results show that CCK has anti-opioid activity in PAG and that tolerance to MOR in PAG can be prevented or reversed if CCK receptors are blocked with PRO. Finally, opioid tolerance induced by repeated systemic MOR injections (5mg/kg intraperitoneal ) was reversed by a single microinjection of PRO into PAG. This emphasizes the central importance of PAG in the MOR/CCK interactions that lead to opioid tolerance.

Puerperal blockade of cholecystokinin (CCK1) receptors disrupts maternal behavior in lactating rats.

Blockade of cholecystokinin (CCK) receptors potentiates the morphine-induced disruption of maternal behavior. The present study was undertaken to determine whether treatment with lorglumide, a CCK1 antagonist during late pregnancy and early lactation can influence the maternal behavior during lactation. A possible influence of this treatment on general activity was also assessed. Twenty-seven female Wistar rats were pretreated with lorglumide (1.0mg/kg/day; sc) or saline for seven days, starting on the 17th d of pregnancy. After the withdrawal of this treatment, animals were acutely challenged with saline on day 5 and with morphine sulfate (3.0mg/kg; sc) on days 6,10, and 17 of lactation. Groups were pretreated with saline and challenged with saline (group SS) and morphine (group SM), pretreated with lorglumide and challenged with saline (group LS) and morphine (group LM). Animals were also tested for general activity on days 25 and 33 postpartum after an acute challenge with saline and morphine, respectively. Maternal behavior testing began 30 min after the acute injections at which time pups were placed throughout each mother's cage. Latencies for pup retrieval, grouping, crouching and for full maternal behavior responses were scored. Lorglumide pretreatment inhibited maternal behavior of LS vs SS group and potentiated the morphine-induced disruption of this behavior in all days of test (LM vs SM group). No significant differences were found in general activity on days 25 and 33 postpartum. These data suggest that blockade of CCK1 receptors during puerperal period has long-term implications for maternal behavior.

Interaction of serotonin and cholecystokinin in the lateral parabrachial nucleus to control sodium intake.

Serotonin [5-hydroxytryptamine (5-HT)] and CCK injected into the lateral parabrachial nucleus (LPBN) inhibit NaCl and water intake. In this study, we investigated interactions between 5-HT and CCK into the LPBN to control water and NaCl intake. Male Holtzman rats with cannulas implanted bilaterally in the LPBN were treated with furosemide + captopril to induce water and NaCl intake. Bilateral LPBN injections of high doses of the 5-HT antagonist methysergide (4 microg) or the CCK antagonist proglumide (50 microg), alone or combined, produced similar increases in water and 1.8% NaCl intake. Low doses of methysergide (0.5 microg) + proglumide (20 microg) produced greater increases in NaCl intake than when they were injected alone. The 5-HT(2a/2c) agonist 2,5-dimetoxy-4-iodoamphetamine hydrobromide (DOI; 5 microg) into the LPBN reduced water and NaCl intake. After proglumide (50 microg) + DOI treatment, the intake was not different from vehicle treatment. CCK-8 (1 microg) alone produced no effect. CCK-8 combined with methysergide (4 microg) reduced the effect of methysergide on NaCl intake. The data suggest that functional interactions between 5-HT and CCK in the LPBN may be important for exerting inhibitory control of NaCl intake.

Differential role of cholecystokinin receptor subtypes in opioid modulation of ongoing maternal behavior.

Cholecystokinin (CCK) can have effects opposite those of opioids. The present study was undertaken to determine whether peripheral injections of antagonists of the CCK1 receptor (lorglumide) and the CCK2 receptor (L-365,260) can influence the effects of morphine on maternal behavior during lactation. A total of 110 female Wistar rats were tested on days 5 and 6 postpartum. Groups were randomly assigned to morphine vehicle (MV-SC) + saline (S-IP), MV + lorglumide (LOR: 1.0 or 10.0 mg/kg), MV + L-365,260 (10 mg/kg), morphine chlorhydrate (MC: 7.0 mg/kg) + S, MC + LOR (1.0 or 10.0 mg/kg), and MC + L-365,260 (1.0 or 10 mg/kg). Maternal behavior testing was started 30 min after the injections, at which time pups were placed in the home cage of their mother. Latencies for retrieval, grouping, and crouching responses were scored. The results show that both lorglumide and L-365,260 potentiated the MC-induced inhibition of maternal behavior. In addition L-365,260 treatment alone inhibited maternal behavior. Blockade of both the CCK1 and CCK2 receptors potentiated the morphine-induced disruption of maternal behavior, while CCK2 antagonism alone also inhibited this behavior. The results suggest that CCK antagonism of opioid-induced disruption of maternal behavior occurs due to the action of CCK on both CCK1 and CCK2 receptor subtypes.

Cholecystokinin actions in the parabrachial nucleus: effects on thirst and salt appetite.

The present study investigated the effects of bilateral injections of the nonselective CCK receptor antagonist proglumide or CCK-8 into the lateral parabrachial nuclei (LPBN) on the ingestion of 0.3 M NaCl and water induced by intracerebroventricular injection of ANG II or by a combined treatment with subcutaneous furosemide (Furo) + captopril (Cap). Compared with the injection of saline (vehicle), bilateral LPBN injections of proglumide (50 micrograms . 200 nl-1 . site-1) increased the intake of 0.3 M NaCl induced by intracerebroventricular ANG II (50 ng/1 microliter). Bilateral injections of proglumide into the LPBN also increased ANG II-induced water intake when NaCl was simultaneously available, but not when only water was present. Similarly, the ingestion of 0.3 M NaCl and water induced by the treatment with Furo (10 mg/kg) + Cap (5 mg/kg) was increased by bilateral LPBN proglumide pretreatment. Bilateral CCK-8 (0.5 microgram . 200 nl-1 . site-1) injections into the LPBN did not change Furo + Cap-induced 0.3 M NaCl intake but reduced water consumption. When only water was available after intracerebroventricular ANG II, bilateral LPBN injections of proglumide or CCK-8 had no effect or significantly reduced water intake compared with LPBN vehicle-treated rats. Taken together, these results suggest that CCK actions in the LPBN play a modulatory role on the control of NaCl and water intake induced by experimental treatments that induce hypovolemia and/or hypotension or that mimic those states.

Plasma cortisol levels in captive wild felines after chemical restraint

Eight Panthera onca (Po), 13 Felis concolor (Fc), Felis yagouaroundi (Fy) 7 Felis tigrina (Ft) and 5 Felis pardalis (Fp) specimens from SÒo Paulo State zoos were used. All animals were restrained with darts containing 10 mg/kg ketamine and 1 mg/kg xylazine. Venous blood samples were collected as soon as possible (within 15-20 min) and serum was frozen until the time for cortisol quantification. Cortisol was determined using a solid phase radioimmunoassay with and intra-assay coefficient of 8.51 percent. Data were analyzed statistically by the Kruskal-Wallis test, followed by Dunn´s multiple comparisons test, and the one-sample t-test, with the level of significance set at P<0.05. Data are reported as means + SEM. Cortisol levels differed among the captive felines: Po = 166 + 33a, Fc = 670 + 118b, Fy = 480 + 83b, Ft = 237 + 42ab, Fp = 97 + 12a nmol/l (values followed by different superscript letters were significantly different (P<0.001). Since most of the veterinary procedures on these species involve chemical restraint, these results show the necessity of preventive measures in order to minimize the effect of restraint stress on more susceptible species.

Plasma cortisol levels in captive wild felines after chemical restraint.

Eight Panthera onca (Po), 13 Felis concolor (Fc), 7 Felis yagouaroundi (Fy), 7 Felis tigrina (Ft) and 5 Felis pardalis (Fp) specimens from São Paulo State zoos were used. All animals were restrained with darts containing 10 mg/kg ketamine and 1 mg/kg xylazine. Venous blood samples were collected as soon as possible (within 15-20 min) and serum was frozen until the time for cortisol quantification. Cortisol was determined using a solid phase radioimmunoassay with an intra-assay coefficient of 8.51%. Data were analyzed statistically by the Kruskal-Wallis test, followed by Dunn's multiple comparisons test, and the one-sample t-test, with the level of significance set at P < 0.05. Data are reported as means +/- SEM. Cortisol levels differed among the captive felines: Po = 166 +/- 33a, Fc = 670 +/- 118b, Fy = 480 +/- 83b, Ft = 237 +/- 42ab, Fp = 97 +/- 12a nmol/l (values followed by different superscript letters were significantly different (P < 0.001)). Since most of the veterinary procedures on these species involve chemical restraint, these results show the necessity of preventive measures in order to minimize the effect of restraint stress on more susceptible species.

Inmovilazación de venados cola blanca (Odocoileus virginianus) utilizando una mezcla de xilazina y ketamina / Immobilization of white-tailed deer (Odocoileus virginianus) with ketamine- xilazine mix

Con la finalidad de evaluar la utilidad de usar una mezcla a dosis constantes (250 mg de xilazina + 100 mg de keatmina/animal) para inmovilizar venados cola blanca (Odocoileus virginianus), se utlizó un rifle "Dist-Inyect" calibre 32 con adaptador de cargas explosivas 22 para proyectar el dardo vector de la mezcla de drogas. Después de una inyección por vía intramuscular (IM), se logró inmovilizar 5 animales entre los 6 min. y 37 min. (prom. 28 min).Con la aplicación por vía endovenosa de 0,1-02 mg. de sulfato de atropina/Kg. de peso corporal, los venados se recuperaron satisfactoriamente entre los 89 min. y 150 min. Tomando como base las ventajas expuestas en el trabajo, se conclute que aún a concentraciones bajas constantes, la mezcla es sumamente útil, confiable y segura para inmovilizar venados silvestres. Para mejorar la técnica se recomienda aumentar en un 20 por ciento la concentración de ambas drogas y usar clorhidrato de yohimbina como antídoto

[Antigastrin therapy in gastric ulcer]. / Terapia antigastrínica en la enfermedad ulcerosa

A brief review of the role of gastrin on gastric secretion and its influence in the genesis of peptic ulcer is made. A report is made of the pharmacological studies of Proglumida and its antigastrin action and the interest its association with Hioscin Butil-Bromuro may represent in the antiulcer therapy. A study is made of 26 patients submitted to a general treatment for peptic ulcer this drug together with a bland diet and psychotherapy. The results were: 19 (73%) cases cured; 6 (23%) cases improved; no results in 1 (4%) case. No secondary side effects appear and the symptomatic response appears 8 days after the treatment is initiated. The dosis used is of 2 tablets before the 3 main meals. Each tablet contains 250 mg of Proglumide and 10 mg of Hioscin Butil-Bromuro. It is considered useful in the antiulcer therapy to have available a drug which can control the physiological effects of gastrin and from this point of view its action is different from that of the antiacids and anticolinergics.

[Clinical evaluation of the use of proglumide in the treatment of the peptic ulcer semebrome]. / Valoración clínica del uso de la proglumida en el tratamiento del sindrome ulceroso

The authors have made a clinical evaluation of Proglumida in 27 patients suffering from Peptic ulcer. Proglumida was administered orraly, 2 tables of 200 mg 3 times a day, 1.200 mg in 24 hours, during a period varying from 21 to 28 days. The painful symptoms improved in 96% of the pain occurred in 59% during the first 7 days of treatment. The dispeptic symptoms improved in all cases, disappearing completely in 74%, but in a slower fashion than the pain, and in 68% of the cases only from the second week of treatment onward. The objectivation of the pain by palpation of the epigastrium improved in all cases and did so in a significant form in 59% of the cases during the first seven days of treatment. No undesireable side effects have been observed in any of the cases. We believe that Proglumida is a pharmacological drug of positive action in the treatment of the ulcer syndrome, because of its favorable action and the absence of secondary side effects.