The effects of therapeutic touch and music on sleep quality, menopausal symptoms, and quality of life in menopausal women.

OBJECTIVES: This study aimed to examine the effects of therapeutic touch (TT) and music on sleep quality, menopausal symptoms, and quality of life in menopausal women. METHODS: This study was carried out in an experimental model with a pretest, a posttest, and a control group. The study was completed with a total of 108 menopausal women in the TT, music, and control groups. Data were collected using a Participant Information Form, the Pittsburgh Sleep Quality Index, the Menopause Rating Scale, and the Menopause-Specific Quality of Life Scale. TT was applied in the TT group once a week for 4 weeks, and the music group was asked to listen to music for 30 minutes before bedtime every day for 4 weeks. Posttest data were collected in all groups 4 weeks after the pretest. The χ 2 , analysis of covariance, post hoc tests, and partial η2 methods were used to analyze the collected data. RESULTS: When the effect of the pretest scores was adjusted, compared with the control group, there were statistically significant differences in the posttest scores of the participants in both the TT and music groups in the Pittsburgh Sleep Quality Index dimensions of subjective sleep quality ( P < 0.001), sleep latency ( P ≤ 0.001), and sleep disturbances ( P < 0.05). When the effect of the pretest scores was adjusted, compared with the control group, there were statistically significant differences in the posttest scores of the participants in both the TT and music groups in the Menopause Rating Scale and Menopause-Specific Quality of Life Scale ( P < 0.001). CONCLUSIONS: It was concluded that TT and music increased sleep quality (subjective sleep quality, sleep latency, and sleep disturbances) and quality of life and reduced menopausal symptoms.

Effects of Probiotic Bacteria on Central Neuronal Activation in Experimental Colitis.

BACKGROUND: Brain-gut axis dysregulation is observed in inflammatory bowel disease. However, the effect of altered gut flora on neuro- immunomodulation and its role in the pathogenesis of inflammatory bowel disease are unknown. The aims of this study are to determine (i) whether colitis modifies the expression of c-fos, a marker of general neuronal activation in the brain and (ii) whether this activation could be modulated by probiotic bacteria. METHODS: In this study, 28 Sprague-Dawley rats were divided into 4 groups: colitis-probiotic group, non-colitis-fed-control group receiv- ing probiotic Lactobacillus delbrueckii subsp. Bulgaricus B3 strain for 7 days, colitis group, and sham group receiving only sodium chlo- ride. Colitis was induced by intracolonic administration of trinitrobenzene sulfonic acid-ethanol. The expression of c-fos was detected by immunohistochemistry in the brain tissue. Cytokines and inflammatory mediators were analyzed in the plasma. Histological scores and oxidative status were analyzed in the colon samples. RESULTS: The inflammatory response was accompanied by increased levels of cytokines, lipid peroxidation activities, c-fos expression in the medial nucleus of the amygdala, and decreased levels of antioxidant enzymes in the colitis (P < .001). Probiotic treatment reversed those effects. Also, histopathologic scores were significantly lower in the probiotic-treated groups compared to the colitis group (P = .035). In contrast, the expression of c-fos was significantly increased in the paraventricular nucleus of hypothalamus in the probiotic- treated rats (P < .001). CONCLUSION: Colitis and intestinal inflammation are associated with the activation of neurons in the limbic system creating stress-like effects in the brain. Probiotics diversely modulate limbic response and hypothalamic axis activity in addition to protective effects in inflammation.

Mast cell activation ameliorates pentylenetetrazole-induced seizures in rats: The potential role for serotonin.

Neuroinflammation plays a key role in the pathogenesis of epilepsy, but the underlying mechanisms are not well understood. Mast cells are multifunctional immune cells that are also activated by stress. The effects of activated mast cells on epileptogenesis are not yet known. This study investigated the effects and mechanisms of compound 48/80-stimulated mast cell activation on pentylenetetrazole-induced epileptic seizures in rats. Male Wistar rats were separated into seven groups (n = 12). Group-1(NS+PTZ) received intraperitoneal saline solution, while groups 2(C-48/80+PTZ-1), 3(C-48/80+PTZ-2), and 4(C-48/80+PTZ-3) received compound-48/80 at doses of 0.5, 1, and 2 mg/kg, respectively, 30 min before 45 mg/kg pentylenetetrazole administration. Similarly, Group-5(Cr+C-48/80+PTZ) received 10 mg/kg cromolyn plus 2 mg/kg compound-48/80 before pentylenetetrazole, and Group-6(MC Dep+C-48/80+PTZ) was exposed to a mast cell-depletion process, and then received 2 mg/kg compound-48/80. Group-7(5-HT+PTZ) received 10 mg/kg serotonin. Seizure stages were evaluated using Racine's scale. Compound-48/80 at 2 mg/kg induced anticonvulsive effects against pentylenetetrazole-induced seizures by extending onset-times of both myoclonic-jerk and generalized tonic-clonic seizures (p = 0.0001), and by shortening the duration of generalized tonic-clonic seizure (p = 0.008). These effects were reversed by cromolyn (p = 0.0001). These effects were not observed in mast cell-depleted rats. Similarly to compound 48/80, serotonin also exhibited anticonvulsive effects against seizures (p < 0.05). Compound 48/80 acts as an anticonvulsant by activating mast cells in a dose-dependent manner. The anticonvulsive effects of mast cell activation may be mediated by serotonin. Mast cell activation may therefore provide protective activity against seizures under appropriate circumstances.

The Potential Therapeutic Effects of Agmatine, Methylprednisolone, and Rapamycin on Experimental Spinal Cord Injury.

OBJECTIVE: In spinal cord injury (SCI), the primary mechanical damage leads to a neuroinflammatory response and the secondary neuronal injury occurs in response to the release of reactive oxygen species (ROS). In addition to the suppression of inflammation, autophagy plays a significant role in the survival of neurons during secondary SCI. The present study aimed to examine the anti-inflammatory and autophagic effects of agmatine and rapamycin in SCI and to compare the results with methylprednisolone (MP) used in the clinic. MATERIALS AND METHODS: In this animal-based experimental study, thirty adult male Sprague-Dawley rats were randomly divided into five groups as sham-control, injury, injury+MP, injury+rapamycin, injury+agmatine groups. SCI was induced by compressing the T7-8-9 segments of the spinal cord, using an aneurysm clip for one minute, and then rats were treated daily for 7 days. Seven days post-treatment, damaged spinal cord tissues of sacrificed rats were collected for microscopic and biochemical examinations using histopathologic and transmission electron microscope (TEM) scores. Malondialdehyde (MDA) and glutathione peroxidase (GPx) levels were spectrophotometrically measured. RESULTS: The results of this study showed that the damaged area was smaller in the rapamycin group when compared to the MP group. Many autophagic vacuoles and macrophages were observed in the rapamycin group. Degeneration of axon, myelin, and wide edema was observed in SCI by electron microscopic observations. Fragmented myelin lamellae and contracted axons were also noted. While MDA and GPx levels were increased in the injury group, MDA levels were significantly decreased in the agmatine and MP groups, and GPx levels were decreased in the rapamycin group. CONCLUSION: The results of our study confirmed that rapamycin and agmatine can be an effective treatment for secondary injury of SCI.

Thymoquinone Inhibits Neurogenic Inflammation Underlying Migraine Through Modulation of Calcitonin Gene-Related Peptide Release and Stabilization of Meningeal Mast Cells in Glyceryltrinitrate-Induced Migraine Model in Rats.

Two main contributors of sterile neurogenic inflammation underlying migraine pain, calcitonin gene-related peptide (CGRP), and meningeal mast cells (MMCs) play a key role in the activation of the inflammatory cascade resulting in the sensitization of trigeminal nociceptors. It is well established that phytochemical agent thymoquinone exhibits multiple anti-inflammatory effects in different in vitro and in vivo models of neuroinflammation. But its effects on the CGRP release and meningeal mast cells are unknown. In the present study, we investigated the effects of thymoquinone on the CGRP release in migraine-related strategic structures which are crucial targets for anti-migraine drugs, and on the MMCs in glyceryl trinitrate (GTN)-induced in vivo migraine model as well as in the ex vivo meningeal preparations in rats. Anti-inflammatory thymoquinone ameliorated GTN-stimulated CGRP levels in plasma, and migraine-related structures including trigeminal ganglion and brainstem; moreover, thymoquinone inhibited degranulation of MMCs and prevented the increase in the number of MMCs in GTN-induced in vivo migraine model. However, in the ex vivo meningeal preparations, thymoquinone did not inhibit the GTN-induced CGRP release from trigeminal meningeal afferents. Our findings suggest that thymoquinone mediates modulation of CGRP release in trigeminal ganglion neurons and brainstem, and stabilization of MMCs. Thus, thymoquinone may be a promising candidate to prevent the meningeal neurogenic inflammation and consequently migraine.

Shared Fate of Meningeal Mast Cells and Sensory Neurons in Migraine.

Migraine is a primary headache disorder which has complex neurogenic pathophysiological mechanisms still requiring full elucidation. The sensory nerves and meningeal mast cell couplings in the migraine target tissue are very effective interfaces between the central nervous system and the immune system. These couplings fall into three categories: intimacy, cross-talk and a shared fate. Acting as the immediate call-center of the neuroimmune system, mast cells play fundamental roles in migraine pathophysiology. Considerable evidence shows that neuroinflammation in the meninges is the key element resulting in the sensitization of trigeminal nociceptors. The successive events such as neuropeptide release, vasodilation, plasma protein extravasation, and mast cell degranulation that form the basic characteristics of the inflammation are believed to occur in this persistent pain state. In this regard, mast cells and sensory neurons represent both the target and source of the neuropeptides that play autocrine, paracrine, and neuro-endocrine roles during this inflammatory process. This review intends to contribute to a better understanding of the meningeal mast cell and sensory neuron bi-directional interactions from molecular, cellular, functional points of view. Considering the fact that mast cells play a sine qua non role in expanding the opportunities for targeted new migraine therapies, it is of crucial importance to explore these multi-faceted interactions.

Activation of P2X7 Receptors in Peritoneal and Meningeal Mast Cells Detected by Uptake of Organic Dyes: Possible Purinergic Triggers of Neuroinflammation in Meninges.

Extracellular ATP activates inflammasome and triggers the release of multiple cytokines in various immune cells, a process primarily mediated by P2X7 receptors. However, the expression and functional properties of P2X7 receptors in native mast cells in tissues such as meninges where migraine pain originates from have not been explored. Here we report a novel model of murine cultured meningeal mast cells and using these, as well as easily accessible peritoneal mast cells, studied the mechanisms of ATP-mediated mast cell activation. We show that ATP induced a time and dose-dependent activation of peritoneal mast cells as analyzed by the uptake of organic dye YO-PRO1 as well as 4,6-diamidino-2-phenylindole (DAPI). Both YO-PRO1 and DAPI uptake in mast cells was mediated by the P2X7 subtype of ATP receptors as demonstrated by the inhibitory effect of P2X7 antagonist A839977. Consistent with this, significant YO-PRO1 uptake was promoted by the P2X7 agonist 2',3'-O-(benzoyl-4-benzoyl)-ATP (BzATP). Extracellular ATP-induced degranulation of native and cultured meningeal mast cells was shown with Toluidine Blue staining. Taken together, these data demonstrate the important contribution of P2X7 receptors to ATP-driven activation of mast cells, suggesting these purinergic mechanisms as potential triggers of neuroinflammation and pain sensitization in migraine.

4-(3,4-dihydroxybenzoyloxymethyl)phenyl-O-ß-D-glucopyranoside effect in liver regeneration.

Following an injury or resection, the mammalian liver has the capacity to regain its former volume and functioning by restoring itself. Studies have demonstrated that antioxidants play a role in hepatic regeneration. This study investigated the effect of 4-(3,4-dihydroxybenzoyloxymethyl) phenyl-O-ß-D-glucopyranoside (PG) obtained from Origanum micranthum on liver regeneration. Sixty Wistar Albino rats were used. In the sham-operated group, a midline abdominal laparotomy was performed without hepatectomy. In the partial hepatectomy (PHx) group, the median and left lateral lobes were removed. Rats in the PHx group received 20 mg/kg/day PG intraperitoneally before being sacrificed at 24, 48, and 72 hrs, and 7 days later. Liver tissues were collected for immunohistochemical analysis and electron microscopic evaluation. We found an increase in mitotic index, and the numbers of Ki-67 stained hepatocytes in all PHx early stage groups (24 hr, 48hr, 72 hr), but not in 7-day groups. The regeneration mediators eNOS, iNOS, TNF-α and NF-κB were shown to increase in PHx groups. This increase was more prominent dependening on time. In the PHx treatment (PHx+PG) groups, while eNOS was still high, iNOS, TNF-α and NF-κB had decreased. The apoptotic index was markedly high in the PHx groups; this was prevented by PG treatment. These findings were supported by the ultrastructural results. Our findings indicate that PG supports liver regeneration, hepatocyte proliferation, reduced liver damage, and inflammatory mediators following PHx.

Salmon calcitonin ameliorates migraine pain through modulation of CGRP release and dural mast cell degranulation in rats.

The exact mechanism of migraine pathophysiology still remains unclear due to the complex nature of migraine pain. Salmon calcitonin (SC) exhibits antinociceptive effects in the treatment of various pain conditions. In this study, we explored the mechanisms underlying the analgesic effect of salmon calcitonin on migrane pain using glyceryltrinitrate (GTN)-induced model of migraine and ex vivo meningeal preparations in rats. Rats were intraperitoneally administered saline, GTN (10 mg/kg), vehicle, saline + GTN, SC (50 µg/kg) + GTN, and SC alone. Also, ex vivo meningeal preparations were applied topically 100 µmol/L GTN, 50 µmol/L SC, and SC + GTN. Calcitonin gene-related peptide (CGRP) contents of plasma, trigeminal neurons and superfusates were measured using enzyme-immunoassays. Dural mast cells were stained with toluidine blue. c-fos neuronal activity in trigeminal nucleus caudalis (TNC) sections were determined by immunohistochemical staining. The results showed that GTN triggered the increase in CGRP levels in plasma, trigeminal ganglion neurons and ex vivo meningeal preparations. Likewise, GTN-induced c-fos expression in TNC. In in vivo experiments, GTN caused dural mast cell degranulation, but similar effects were not seen in ex vivo experiments. Salmon calcitonin administration ameliorated GTN-induced migraine pain by reversing the increases induced by GTN. Our findings suggested that salmon calcitonin could alleviate the migraine-like pain by modulating CGRP release at different levels including the generation and conduction sites of migraine pain and mast cell behaviour in the dura mater. Therefore salmon calcitonin may be a new therapeutic choice in migraine pain relief.

The effect of kisspeptin on spermatogenesis and apoptosis in rats.

BACKGROUND/AIM: To study the effect of kisspeptin, a gonadotropin release stimulator, on the testicular tissue of the rat. MATERIALS AND METHODS: Four groups were formed as follows: control, Kiss-10 501397645907nmol administration for 1 day, Kiss-10 administration for 13 days, and one last group kept for 7 days following Kiss-10 applied for 13 days. Testicular tissues were stained with hematoxylin-eosin, periodic acid Schiff, Masson trichrome staining, terminal deoxynucleotidyl transferased UTP nick-end labeling, and Ki-67 immune staining. Serum testosterone levels were determined. RESULTS: Serum testosterone level increased following acute application, while it was reduced by chronic treatment. Spermatogenic cells as stained by Ki-67 and TUNEL increased in the treated groups compared to the controls. Following a 7-day rest after treatment, a decrease in testosterone levels and Ki-67-stained cell numbers and an increase in TUNEL-stained cells were observed. Leydig cells showed increased vacuolization in the Kiss-1 group. Leydig cell vacuolization continued in the Kiss (13) group and was reduced in the Kiss (13 + 7) group. CONCLUSION: Kiss-10 increased spermatogenic cell proliferation, while testosterone level and proliferation decreased and apoptosis increased during the waiting period.

Serotonergic mechanisms of trigeminal meningeal nociception: Implications for migraine pain.

Serotonergic mechanisms play a central role in migraine pathology. However, the region-specific effects of serotonin (5-HT) mediated via multiple types of receptors in the nociceptive system are poorly understood. Using extracellular and patch-clamp recordings, we studied the action of 5-HT on the excitability of peripheral and central terminals of trigeminal afferents. 5-HT evoked long-lasting TTX-sensitive firing in the peripheral terminals of meningeal afferents, the origin site of migraine pain. Cluster analysis revealed that in majority of nociceptive fibers 5-HT induced either transient or persistent spiking activity with prevailing delta and theta rhythms. The 5-HT3-receptor antagonist MDL-72222 or 5-HT1B/D-receptor antagonist GR127935 largely reduced, but their combination completely prevented the excitatory pro-nociceptive action of 5-HT. The 5-HT3 agonist mCPBG activated spikes in MDL-72222-dependent manner but the 5HT-1 receptor agonist sumatriptan did not affect the nociceptive firing. 5-HT also triggered peripheral CGRP release in meninges, which was blocked by MDL-72222.5-HT evoked fast membrane currents and Ca2+ transients in a fraction of trigeminal neurons. Immunohistochemistry showed expression of 5-HT3A receptors in fibers innervating meninges. Endogenous release of 5-HT from degranulated mast cells increased nociceptive firing. Low pH but not histamine strongly activated firing. 5-HT reduced monosynaptic inputs from trigeminal Aδ- and C-afferents to the upper cervical lamina I neurons and this effect was blocked by MDL-72222. Consistent with central inhibitory effect, 5-HT reduced CGRP release in the brainstem slices. In conclusion, 5-HT evokes powerful pro-nociceptive peripheral and anti-nociceptive central effects in trigeminal system transmitting migraine pain.

Vasoactive Intestinal peptide modulates c-Fos activity in the trigeminal nucleus and dura mater mast cells in sympathectomized rats.

Neurogenic inflammation in the dura mater caused by trigeminal nociceptive activation has been implicated in the pathophysiology of migraine. Vasoactive intestinal polypeptide (VIP) is a powerful neuroprotective neuropeptide that can modulate mast cell behavior. Migraine is also associated with sympathetic insufficiency. This study investigates the effects of VIP on the number of mast cells in the dura mater and on c-Fos expression in the trigeminal nucleus of sympathectomized rats. Experiments were carried out with 32 Sprague-Dawley male rats with body weights of 200-250 g. In the sympathectomized group, the left superior cervical sympathetic ganglion was removed. In the sympathectomized + VIP group, postoperative VIP 25 ng/kg/day (0.2 ml) was administered for 5 days. In the sham group, the ganglion and nerves were exposed but not dissected. Dura maters were stained with toluidine blue, and brainstems were labeled by indirect immunohistochemistry for c-Fos. Sympathectomy significantly increased the number of mast cells in both the ipsilateral and the contralateral dura mater (P < 0.001). VIP decreased the number of mast cells in both sides of the dura mater in sympathectomized rats. VIP also decreased c-Fos expression in the ipsilateral trigeminal nucleus of sympathectomized rats (P < 0.001). In the context of an experimental superior cervical ganglionectomy model of migraine, VIP is an efficient modulator of neurogenic inflammation of the dura.

The preventive effect of low molecular weight heparin on CCL4-induced necrosis and apoptosis in rat liver.

INTRODUCTION: Heparin having anti-inflammatory and anti-fibrotic properties may have therapeutic effect on liver injury. The present study investigated the effect of low molecular weight heparin (Enoxaparin) on carbon tetrachloride (CCl4) induced hepatic necrosis and apoptosis in rats. MATERIAL AND METHODS: Thirty male rats were divided into 5 groups. Group I: Control; Group II: Olive oil dissolved CCl4 at dose of 1 mL/kg, ip, twice per week; Group III: CCl4 and Enoxaparin at dose of 180 IU/kg, sc, daily; Group IV: Enoxaparin; Group V: Olive oil at dose of 1 mL, ip, twice per week. The liver histology at the forth week was examined by haematoxylin-eosin, Masson.s trichrome, Toluidine blue and Periodic acid schiff stains. Proliferative and apoptotic activities were assessed semi-quantitatively by proliferating cell nuclear antigen (PCNA) and caspase-3 immune staining and TUNEL method. Semi-quantitative values formulated by the equation HSCORE =ΣP(i) (i+1) including both distribution and intensity of staining. Additionally, nidogen and a-smooth muscle actin were labeled by immunohistochemistry. RESULTS: CCl4 group had marked hepatocelluar necrosis around the vena centralis and increased inflammatory cells and mast cells. Hepatocytes showed deposition of lipid droplets, decrease in glycogen, apoptosis, and picnotic or enlarged nuclei. Enoxaparin reduced necrosis, apoptosis, and number of mast cells but had no effect on lipid droplets in hepatocytes. HSCORE.s of caspase-3 and PCNA were also significantly decreased by administration. CONCLUSION: Enoxaparin have beneficial effects against necrosis as well as apoptosis at the early stage of CCL4 induced liver injury.

The effects of vasoactive intestinal peptide on dura mater nitric oxide levels and vessel-contraction responses in sympathectomized rats.

Nitric oxide (NO) and neurogenic inflammation in dura mater due to nociceptor activation has been implicated for pathophysiology of primary headache disorders. Development of migraine has also been observed in patients treated with ganglion blockage for sympathetic reflex dystrophy. Vasoactive intestinal peptide (VIP) is an antioxidant, anti-inflammatory, and neuroprotective neuropeptide. This study is intended to investigate the effects of VIP on dura mater NO levels and vessel-contraction responses in sympathectomized rats. In the experiments, 30 male rats in five groups were used. Group 1 sympathectomized: under anesthesia, superior cervical sympathetic ganglion was removed via incision at the center line in the neck area. Group 2 sympathectomized + VIP: postoperative VIP of 25 ng/kg/day (0.2 ml) intraperitoneally administered to the rats exposed to the same operations for 5 days. Group 3 sham: ganglia and nerves were exposed but not dissected. Group 4 control: no treatment was done. Group 5 VIP: only VIP was administered for 5 days. Sympathectomy induced a significant increase in dura mater NO levels and VIP decreased NO to control levels and increased the norepinephrine vessel-contraction responses of sympathectomized rats. VIP is an efficient NO modulator in superior cervical ganglionectomized rats.

Sympathetic skin responses of the face and neck evoked by electrical stimulation.

The sympathetic skin responses (SSRs) were recorded from different facial regions and neck in 25 subjects evoked by electrical stimulation of the median nerve at the wrist. Recordings from all regions were cross-compared with each other and within right and left sides individually. In one subject postauricular SSR, and in another subject upper lip SSR could not be elicited on both sides. Other responses could be obtained in all the remaining subjects. In 11 subjects, the responses did not appear by the first stimulus, and began to appear by repeated stimuli. Mean latencies and the highest amplitudes of the responses were similar for both sides. Gradual amplitude increase was observed in the first three or four set of responses in 20 subjects, although the stimulus intensity was constant. In conclusion, face and neck SSRs are symmetric, can be evoked by electrical stimulation and can be used to investigate the sympathetic innervation of these areas.

Passage of VIP/PACAP/secretin family across the blood-brain barrier: therapeutic effects.

In recent years, VIP/PACAP/secretin family has special interest. Family members are vasoactive intestinal peptide (VIP), pituitary adenylate cyclase-activating polypeptide (PACAP), secretin, glucagon, glucagon like peptide-1 (GLP(1)), GLP(2), gastric inhibitory peptide (GIP), growth hormone releasing hormone (GHRH or GRF), and peptide histidine methionine (PHM). Most of the family members present both in central nervous system (CNS) and in various peripheral tissues. The family members that are released into blood from periphery, especially gut, circulate the brain and they can cross the blood brain barrier. On the other hand, some of the members of this family that present in the brain, can cross from brain to blood and reach the peripheral targets. VIP, secretin, GLP(1), and PACAP 27 are transported into the brain by transmembrane diffusion, a non-saturable mechanism. However, uptake of PACAP 38 into the brain is saturable mechanism. While there is no report for the passage of GIP, GLP(2), and PHM, there is only one report that shows, glucagon and GHRH can cross the BBB. The passage of VIP/PACAP/secretin family members opens up new horizon for understanding of CNS effects of peripherally administrated peptides. There is much hope that those peptides may prove to be useful in the treatment of serious neurological diseases such as Alzheimer's disease, amyotropic lateral sclerosis, Parkinson's disease, AIDS related neuropathy, diabetic neuropathy, autism, stroke and nerve injury. Their benefits in various pathophysiologic conditions undoubtly motivate the development of a novel drug design for future therapeutics.

Protective effect of vasoactive intestinal peptide on testicular torsion-detorsion injury: association with heparin-containing mast cells.

OBJECTIVES: To elucidate the action of vasoactive intestinal peptide (VIP) on detorsion injury and the heterogeneity of mast cells in the testes of rats. METHODS: Prepubertal male Sprague-Dawley rats were used in six groups. Group 1 was the control group (sham operation); group 2 had 2 hours of torsion; group 3, 2 hours of torsion and 1 hour of detorsion after administration of saline; group 4 had 2 hours of torsion and 4 hours of detorsion after administration of saline; group 5, 2 hours of torsion and 1 hour of detorsion after administration of intraperitoneal VIP (25 ng/kg); and group 6, 2 hours of torsion and 4 hours of detorsion after intraperitoneal VIP. The 2 hours of torsion was created by rotating the right testis 720 degrees in a clockwise direction. VIP (25 ng/kg) was injected intraperitoneally 1 minute before the 1 and 4 hours of detorsion. At the end of the experiment, catalase enzyme activity was measured polarographically, and superoxide dismutase, malondialdehyde, and protein were measured spectrophotometrically. Nitric oxide was measured by capillary electrophoresis in the testicular tissue. Routine histologic examination of testicular mast cells was done under light microscopy; the histochemistry was also analyzed. RESULTS: Torsion significantly induced oxidative stress, mast cell degranulation, and tissue damage. Detorsion attenuated oxidative stress without any diminution of the histologic damage to the tissue. VIP significantly protected the testicular tissue from detorsion injury. It also inhibited mast cell activity while increasing the heparin content. CONCLUSIONS: VIP can protect testicular tissue from detorsion injury. Heparin-containing mast cells seem to be important mediator cells for this protection.