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Fungi and Water
Published in Chuong Pham-Huy, Bruno Pham Huy, Food and Lifestyle in Health and Disease, 2022
Chuong Pham-Huy, Bruno Pham Huy
In addition, some species of amanita genus like Amanita pantherina and A. muscaria have hallucinogenic effects (96). They contain two constituents called ibotenic acid and muscimol which are responsible for the hallucinogenic effects. Ibotenic acid is a powerful agonist of N-methyl-D-aspartic-acid receptor and muscimol is a potent gamma-aminobutyric acid A agonist (96). The intoxications caused by A. muscaria were long believed to be due to muscarine, but it was demonstrated that muscarine is present in small amounts. People around the world have intentionally eaten A. muscaria or A. pantherina to evoke euphoria and hallucinations (96). The most common symptoms of intoxication are dizziness, drowsiness, motor depression, ataxia, changes in mood, gastrointestinal disturbances, and muscle twitches (96). Fatality due to Amanita pantherina and A. muscaria poisoning is rare. In most cases recovery is complete after 24 hours. The treatment is mainly symptomatic. Cholinesterase inhibitors, benzodiazepines, or phenobarbitone can be used in case of seizures (96).
Central bradykinin receptors in the SHR and blood pressure
Published in H. Saito, Y. Yamori, M. Minami, S.H. Parvez, New Advances in SHR Research –, 2020
Microinjections of bradykinin in structures surrounding the paratrigeminal nucleus produced smaller effects to microinjections in the nucleus suggesting that the pressor effect in the dorsolateral medulla is mediated by the paratrigeminal nucleus (Fior et al., 1993 and unpublished results). In order to demonstrate the participation of the paratrigeminal nucleus in the mediation of the pressor effect, the cell bodies of the nucleus were destroyed by a discreet microinjection of ibotenic acid. Four month old Wistar rats were anasthetized and underwent surgery for streotaxic placing of bilateral cánulas for injections in the paratrigeminal nucleus and a catheter in the abdominal aorta for blood pressure recording. Following the surgery O.S μg of ibotenic acid in 0.05 μg was injected unilateraly in the paratrigeminal nucleus. Two days later animals were challenged with an injection of 12 pmol of bradykinin in the paratrigeminal nucleus on the lesioned and intact side and the blood pressure was recorded. When bradykinin was injected over the lesioned nucleus the pressor effect was abolished, however the response remained unchanged when bradykinin was injected over the intact contralateral nucleus of the same rat (Fig. 2).
Neurobiological Substrates Mediating the Reinforcing Effects of Psychomotor Stimulant and Opiate Drugs
Published in Edythe D. London, Imaging Drug Action in the Brain, 2017
Carol B. Hubner, George F. Koob
Evidence that the nucleus accumbens is an important substrate mediating the reinforcing effects of psychomotor stimulants has led to studies focusing not only on the fibers of passage through this nucleus but also on the efferent anatomical projections through which the nucleus accumbens may influence reinforcement. Significant efferent projections from the nucleus accumbens to the region of the ventral pallidum have been described (Williams et al., 1977; Mogenson et al., 1983), and these fibers contain GABA, enkephalin and substance P (Zaborszky et al., 1982). As a result, the role of this region in mediating the reinforcing effects of cocaine was investigated in rats trained to self-administer cocaine on an FR 5 schedule of reinforcement (Hubner and Koob, 1990a). Following the establishment of stable baseline rates of responding, lesions of the ventral pallidal region were produced with the excitotoxin, ibotenic acid. Injection of ibotenic acid into discrete brain regions results in the selective destruction of neurons which have their cell bodies at the site of injection. The behavioral effects of the lesion were assessed using fixed-ratio as well as progressive-ratio schedules.
The White Panther – Rare exposure to Amanita multisquamosa causing clinically significant toxicity
Published in Clinical Toxicology, 2021
V. Vohra, I. V. Hull, K. T. Hodge
Scant literature exists surrounding Amanita multisquamosa exposures. Toxicity has been compared to Amanita muscaria ingestion, with primarily neurological features and mild gastrointestinal (GI) effects [2,3]. Previous cases include a Canadian family who experienced GI symptoms and demonstrated erratic behavior three hours after eating cooked specimens, resembling Amanita muscaria toxicosis [3]. High concentrations of ibotenic acid and muscimol have been found in Amanita multisquamosa samples, supporting comparisons to Amanita muscaria [4]. Ibotenic acid exerts excitatory central nervous system (CNS) effects while muscimol produces CNS depression [5]. Symptoms may appear within 30–120 min and can last 10–24 h [4,5]. Symptomatic and supportive care is indicated [5]. Our patient had a cardiac conduction abnormality of unknown etiology. Comprehensive molecular characterization of other toxins in Amanita multisquamosa has not been elucidated, therefore this exposure cannot be ruled out as a potential cause.
Combination Effects of Forced Mild Exercise and GABAB Receptor Agonist on Spatial Learning, Memory, and Motor Activity in Striatum Lesion Rats
Published in Journal of Motor Behavior, 2019
Shaghayegh Modaberi, Soomaayeh Heysieattalab, Mehdi Shahbazi, Nasser Naghdi
Rats were anesthetized with a combination of ketamine (100 mg/kg of body weight (b.w.) and xylazine intraperitoneally (10 mg/kg b.w. IP). A midline incision was done in the skin overlying the skull. Small holes were drilled using a size ½ burrs in a dental drill set up on a stereotaxic arm into striatum at coordinates: AP = + 0.35, ML = ± 3.05 from bregma and DV =5.5 from dura using a stereotactic atlas (Thomsen et al., 2015). Ibotenic Acid (Sigma-Aldrich) was injected bilaterally via a 1 μl Hamilton Syringe in doses of (5 μg/1 μl) in the striatum (ventral lateral). Hamilton syringe mounted on top of the hole and push slightly forward in target place of striatum during 3 min. The syringe was left to diffuse for a further 2 min before removal and then pulled slowly to the backstop. Sham animals received bilaterally an equal volume of normal saline into the striatum. Finally, the wound was closed with simple sutures. According to a standard stereotaxic atlas (Paxinos, Watson, & Emson, 1980), a guide cannula constructed from stainless steel was implanted into the GPi (2.4 mm posterior, ±2.8 mm lateral from the bregma, 6.8 mm ventral from the skull surface), on either side. The cannula was fixed to the skull with stainless steel screws and dental acrylic. Stainless steel styles were used to keep the cannula sealed.
Toxicity of muscimol and ibotenic acid containing mushrooms reported to a regional poison control center from 2002–2016
Published in Clinical Toxicology, 2019
Michael J. Moss, Robert G. Hendrickson
There are several Amanita mushroom species throughout the world which contain ibotenic acid and muscimol including Amanita. Muscaria (AM), A. pantherina (AP), A. gemmata, A. aprica, and A. regalis [1–3]. AM has been used by various cultures for religious activities, supporting work and physical exercise, and medicinal purposes [4]. Modern usage is generally for recreational and psychoactive effects [5]. Ibotenic acid and muscimol are isoxazole derivatives that resemble the neurotransmitters glutamate and GABA, respectively [6]. Thus, ibotenic acid may induce excitatory effects while muscimol causes sedative effects. There are numerous other chemical constituents in these species of mushrooms that have unknown effects. Muscarine, once thought to be the primary toxin in AM, has been shown to be present only in miniscule quantities [7].