scholarly journals Serotonergic control in initiating defensive responses to unexpected tactile stimuli in the trap-jaw ant Odontomachus kuroiwae

2020 ◽  
Vol 223 (19) ◽  
pp. jeb228874 ◽  
Author(s):  
Hitoshi Aonuma
Keyword(s):  
Oral Administration ◽  
Defensive Behavior ◽  
Tactile Stimulation ◽  
Defensive Response ◽  
Potential Threat ◽  
Defensive Responses ◽  
Tactile Stimuli ◽  
Neuronal Mechanisms ◽  
The Brain ◽  
Unexpected Stimulus

ABSTRACTThe decision to express either a defensive response or an escape response to a potential threat is crucial for insects to survive. This study investigated an aminergic mechanism underlying defensive responses to unexpected touch in an ant that has powerful mandibles, the so-called trap-jaw. The mandibles close extremely quickly and are used as a weapon during hunting. Tactile stimulation to the abdomen elicited quick forward movements in a dart escape in 90% of the ants in a colony. Less than 10% of the ants responded with a quick defensive turn towards the source of stimulation. To reveal the neuronal mechanisms underlying this defensive behavior, the effect of brain biogenic amines on the responses to tactile stimuli were investigated. The levels of octopamine (OA), dopamine (DA) and serotonin (5HT) in the brain were significantly elevated in ants that responded with a defensive turn to the unexpected stimulus compared with ants that responded with a dart escape. Oral administration of DA and 5HT demonstrated that both amines contributed to the initiation of a defensive response. Oral administration of l-DOPA weakly affected the initiation of the defensive turn, while 5-hydroxy-l-tryptophan (5HTP) strongly affected the initiation of defensive behavior. Oral administration of ketanserin, a 5HT antagonist, inhibited the initiation of the defensive turn in aggressive workers, abolishing the effects of both 5HT and 5HTP on the initiation of turn responses. These results indicate that 5HTergic control in the nervous system is a key for the initiation of defensive behavior in the trap-jaw ant.

scholarly journals Serotonergic control in initiating defensive responses to unexpected tactile stimuli in the trap-jaw ant Odontomachus kuroiwae

2020 ◽  
Author(s):  
Hitoshi Aonuma
Keyword(s):  
Oral Administration ◽  
Defensive Behavior ◽  
Control Mechanisms ◽  
Defensive Response ◽  
Potential Threat ◽  
Defensive Responses ◽  
Neuronal Control ◽  
Tactile Stimuli ◽  
The Brain ◽  
Unexpected Stimulus

ABSTRACTA decision to express a defensive response or an escape response to a potential threat is crucial for insects to survive. This study investigated an aminergic mechanism underlying defensive responses to unexpected touch in an ant that has powerful mandibles, the so-called trap-jaw. The mandibles close extremely quickly and are used as a weapon during hunting. Tactile stimulation to the abdomen elicited quick forward movements in a “dart escape” in 90% of the ants in a colony. Less than 10% of the ants responded with a quick “defensive turn” towards the source of stimulation. To reveal the neuronal control mechanisms underlying this defensive behavior, the effects of brain biogenic amines on the responses to tactile stimulus were investigated. The levels of octopamine (OA), dopamine (DA) and serotonin (5HT) in the brain were significantly elevated in ants that responded with a defensive turn to the unexpected stimulus compared to ants that responded with a dart escape. Oral administration of DA and 5HT demonstrated that both amines contributed to the initiation of a defensive response to the stimulus. Oral administration of L-DOPA weakly affected the initiation of the defensive turn, while 5HTP strongly affected the initiation of defensive behavior. Oral administration of an antagonist of 5HT, ketanserin, abolished the effect of 5HTP. These results indicate that endogenous 5HT in the brain has a key role to play in modulating the initiation of defensive behavior in the trap-jaw ant.

Simultaneous Determination of Imatinib and N-Desmethyl Imatinib in Rat Plasma and Tissues Using LC-MS/MS

2019 ◽  
Vol 15 (2) ◽  
pp. 121-129
Author(s):  
Zhi Rao ◽  
Bo-xia Li ◽  
Yong-Wen Jin ◽  
Wen-Kou ◽  
Yan-rong Ma ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Oral Administration ◽  
Parent Drug ◽  
Gradient Elution ◽  
Biological Tissues ◽  
Rat Plasma ◽  
Running Water ◽  
Liver And Kidney ◽  
The Brain

Background: Imatinib (IM) is a chemotherapy medication metabolized by CYP3A4 to Ndesmethyl imatinib (NDI), which shows similar pharmacologic activity to the parent drug. Although methods for determination of IM and/or NDI have been developed extensively, only few observations have been addressed to simultaneously determine IM and NDI in biological tissues such as liver, kidney, heart, brain and bone marrow. Methods: A validated LC-MS/MS method was developed for the quantitative determination of imatinib (IM) and N-desmethyl imatinib (NDI) from rat plasma, bone marrow, brain, heart, liver and kidney. The plasma samples were prepared by protein precipitation, and then the separation of the analytes was achieved using an Agilent Zorbax Eclipse Plus C18 column (4.6 × 100 mm, 3.5 µm) with gradient elution running water (A) and methanol (B). Mass spectrometric detection was achieved by a triplequadrupole mass spectrometer equipped with an electrospray source interface in positive ionization mode. Results: This method was used to investigate the pharmacokinetics and the tissue distributions in rats following oral administration of 25 mg/kg of IM. The pharmacokinetic profiles suggested that IM and NDI are disappeared faster in rats than human, and the tissue distribution results showed that IM and NDI had good tissue penetration and distribution, except for the brain. This is the first report about the large penetrations of IM and NDI in rat bone marrow. Conclusion: The method demonstrated good sensitivity, accuracy, precision and recovery in assays of IM and NDI in rats. The described assay was successfully applied for the evaluation of pharmacokinetics and distribution in the brain, heart, liver, kidney and bone marrow of IM and NDI after a single oral administration of IM to rats.

scholarly journals Hypothalamic perifornical Urocortin-3 neurons modulate defensive responses to a potential threat stimulus

iScience ◽  
2021 ◽  
Vol 24 (1) ◽  
pp. 101908
Author(s):  
Noriko Horii-Hayashi ◽  
Kensaku Nomoto ◽  
Nozomi Endo ◽  
Akihiro Yamanaka ◽  
Takefumi Kikusui ◽  
...  
Keyword(s):  
Potential Threat ◽  
Defensive Responses ◽  
Urocortin 3 ◽  
Threat Stimulus

scholarly journals Decreased defensive reactivity to interoceptive threat after successful exposure-based psychotherapy in patients with panic disorder

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Christoph Benke ◽  
Manuela G. Alius ◽  
Alfons O. Hamm ◽  
Christiane A. Pané-Farré
Keyword(s):  
Panic Disorder ◽  
Primary Diagnosis ◽  
Symptom Improvement ◽  
Defensive Response ◽  
Wait List ◽  
Eyeblink Response ◽  
Waiting Period ◽  
Startle Eyeblink ◽  
Defensive Responses ◽  
Clinically Significant

AbstractPanic disorder (PD) is characterized by a dysfunctional defensive responding to panic-related body symptoms that is assumed to contribute to the persistence of panic symptomatology. The present study aimed at examining whether this dysfunctional defensive reactivity to panic-related body symptoms would no longer be present following successful cognitive behavior therapy (CBT) but would persist when patients show insufficient symptom improvement. Therefore, in the present study, effects of CBT on reported symptoms and defensive response mobilization during interoceptive challenge were investigated using hyperventilation as a respiratory symptom provocation procedure. Changes in defensive mobilization to body symptoms in the course of CBT were investigated in patients with a primary diagnosis of PD with or without agoraphobia by applying a highly standardized hyperventilation task prior to and after a manual-based CBT (n = 38) or a waiting period (wait-list controls: n = 20). Defensive activation was indexed by the potentiation of the amygdala-dependent startle eyeblink response. All patients showed a pronounced defensive response mobilization to body symptoms at baseline. After treatment, no startle reflex potentiation was found in those patients who showed a clinically significant improvement. However, wait-list controls and treatment non-responders continued to show increased defensive responses to actually innocuous body symptoms after the treatment/waiting period. The present results indicate that the elimination of defensive reactivity to actually innocuous body symptoms might be a neurobiological correlate and indicator of successful CBT in patients with PD, which may help to monitor and optimize CBT outcomes.

Effects of long-term oral administration of silver nanoparticles on the cognitive functions of mammals

2021 ◽  
Vol 29 (6) ◽  
pp. 33-38
Author(s):  
Anna Alexandrovna Antsiferova ◽  
Marina Yurievna Kopaeva ◽  
Vyacheslav Nikolaevich Kochkin ◽  
Pavel Konstantinovich Kashkarov
Keyword(s):  
Silver Nanoparticles ◽  
Oral Administration ◽  
Dietary Supplement ◽  
Cognitive Functions ◽  
High Demand ◽  
Gastrointestinal Infections ◽  
Impaired Cognitive Function ◽  
Potential Risks ◽  
The Brain

Introduction. Since the beginning of the XXI century, silver nanoparticles have been widely used in various industries, medicine and pharmaceuticals due to their pronounced antibacterial, antiviral and fungicidal properties. In connection with such a high demand for the use of silver nanoparticles, it is very important to understand the associated potential risks from their use. Materials and methods. In the course of the work, there has been a study of the effects of the long-term oral administration of a commercially produced dietary supplement based on silver nanoparticles with a size of 34 nm and stabilized with polyvinylpyrrolidone in an amount of 50 μg/day/animal on the cognitive functions of C57Bl/6 mice, as well as their accumulation in the brain by the method of instrumental neutron activation analysis. The dietary supplement used is recommended for people as a treatment for gastrointestinal infections. Results. It was found that after 180 days of administration, silver nanoparticles impair long-term contextual memory, and over time, the content of silver in the brain increases. Conclusion. Presumably impaired cognitive function with accumulation of silver in the brains of mice. This poses the risk of prolonged oral use of the silver nanoparticles.

The locust jump. I. The motor programme

1977 ◽  
Vol 66 (1) ◽  
pp. 203-219
Author(s):  
W. J. Heitler ◽  
M. Burrows
Keyword(s):  
High Frequency ◽  
Tactile Stimulation ◽  
The Body ◽  
Flexor Muscle ◽  
Tactile Stimuli ◽  
Extensor Muscles ◽  
Trigger Activity ◽  
Three Stages ◽  
Motor Programme ◽  
Made In

A motor programme is described for defensive kicking in the locust which is also probably the programme for jumping. The method of analysis has been to make intracellular recordings from the somata of identified motornuerones which control the metathoracic tibiae while defensive kicks are made in response to tactile stimuli. Three stages are recognized in the programme. (1) Initial flexion of the tibiae results from the low spike threshold of tibial flexor motorneurones to tactile stimulation of the body. (2) Co-contraction of flexor and extensor muscles followa in which flexor and extensor excitor motoneurones spike at high frequency for 300-600 ms. the tibia flexed while the extensor muscle develops tension isometrically to the level required for a kick or jump. (3) Trigger activity terminates the co-contraction by inhibiting the flexor excitor motorneurones and simultaneously exciting the flexor inhibitors. This causes relaxation of the flexor muscle and allows the tibiae to extend. If the trigger activity does not occur, the jump or kick is aborted, and the tibiae remain flexed.

Neuronal correlates of siphon withdrawal in freely behaving Aplysia

1979 ◽  
Vol 42 (6) ◽  
pp. 1538-1556 ◽  
Author(s):  
J. E. Kanz ◽  
L. B. Eberly ◽  
J. S. Cobbs ◽  
H. M. Pinsker
Keyword(s):  
Low Frequency ◽  
Short Latency ◽  
Moderate Intensity ◽  
Efferent Activity ◽  
Nerve Cuff ◽  
Tactile Stimuli ◽  
Cuff Electrodes ◽  
Neuronal Mechanisms ◽  
Wide Range ◽  
Freely Behaving

1. Central neuronal mechanisms of siphon withdrawal in Aplysia were studied for the first time in intact, freely behaving animals by means of population recordings from implanted whole-nerve cuff electrodes. Intracellular follow-up studies were then conducted when the same animal was reduced to a semi-intact preparation. 2. Background spontaneous activity in the siphon nerve consisted of low-frequency firing of a population of efferent units containing identified siphon motoneurons. 3. Spontaneous patterned bursts of efferent activity occurred irregularly and were associated with all-or-nothing contractions of the parapodia, gill, and siphon. Spontaneous bursts were due to centrally generated activity in the interneuron II (INT II) network, an oscillatory network with endogenous pacemaker properties. 4. In intact animals, even weak tactile stimuli to the siphon typically triggered an INTII burst shortly after the stimulus-locked efferent activity. Thus, the stimulus can phase-advance the INT II oscillator. In semi-intact preparations, short-latency INT II bursts were triggered less less frequently and required more intense stimuli. 5. With weak to moderate-intensity stimuli in intact animals, the presence of short-latency triggered INT II bursts largely determined the duration of the siphon component and amplitude of the gill component of the withdrawal reflex. 6. When stimuli were repeated over a range of interstimulus intervals (from 60 to 1 min), the likelihood of triggering a short-latency INT II burst die not change systematically. Thus, the ability of the siphon stimulus to stably entrain the all-or-none INT II component over a wide range of intervals will interact behaviorally with the decrement of the monosynaptic component of the reflex with repetition.

Tactile Stimulation in Adult Rats Modulates Dopaminergic Molecular Parameters in the Nucleus Accumbens Preventing Amphetamine Relapse.

2022 ◽  
Author(s):  
Domênika Rubert Rossato ◽  
Higor Zuchetto Rosa ◽  
Jéssica Leandra Oliveira Rosa ◽  
Laura Hautrive Milanesi ◽  
Vinícia Garzella Metz ◽  
...  
Keyword(s):  
Nucleus Accumbens ◽  
Tactile Stimulation ◽  
Male Rats ◽  
Adult Rats ◽  
Delta Fosb ◽  
The Central Nervous System ◽  
Molecular Assessment ◽  
Drug Abstinence ◽  
The Brain ◽  
Abstinence Period

Abstract Amphetamine (AMPH) is a psychostimulant drug frequently related to addiction, which is characterized by functional and molecular changes in the brain reward system, favoring relapse development and pharmacotherapies have shown low effectiveness. Considering the beneficial influences of tactile stimulation (TS) in different diseases that affect the central nervous system (CNS), here we evaluated if TS applied in adult rats could prevent or minimize the AMPH-relapse behavior also accessing molecular neuroadaptations in the Nucleus accumbens (NAc). Following AMPH conditioning in the conditioned place preference (CPP) paradigm, male rats were submitted to TS (15-min session, 3 times a day, for 8 days) during the drug abstinence period, which were re-exposed to the drug in the CPP paradigm for additional 3 days for relapse observation and molecular assessment. Our findings showed that besides AMPH relapse; TS prevented the dopamine transporter (DAT), dopamine 1 receptor (D1R), tyrosine hydroxylase (TH), mu opioid receptor (MOR) increase and AMPH-induced delta FosB (ΔFosB). Based on these outcomes, we propose TS as a useful tool to treat psychostimulant addiction, which subsequent to clinical studies; it could be included in detoxification programs together with pharmacotherapies and psychological treatments already conventionally established.

Interneurones in Crab Connectives (Carcinus Maenas (L.)): Giant Fibres

1974 ◽  
Vol 61 (3) ◽  
pp. 593-613
Author(s):  
PETER J. FRASER
Keyword(s):  
Electrical Stimulation ◽  
Carcinus Maenas ◽  
Dendritic Trees ◽  
Tactile Stimuli ◽  
Giant Fibres ◽  
The Brain

Five interneurones with cell bodies and dendritic trees in the brain have axons 40-60µm diameter in one oesophageal connective. The fibres are phasic and multimodal, responding to visual and tactile stimuli. They have complex adaptation properties and two are suppressed completely during certain movements of the animal. The role of the fibres in overt behaviour has not been revealed by electrical stimulation or by examination of output in free walking animals. Several smaller interneurones in the connective are briefly described anatomically and physiologically.

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