lørdag, januar 23, 2021

Cannabis er godt for hjernen

Daily Rush Debat Off-topic Cannabis er godt for hjernen

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  • #0

    SmileyMan3
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    Cannabinoids promote embryonic and adult hippocampus neurogenesis and produce anxiolytic- and antidepressant-like effects
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    The hippocampal dentate gyrus in the adult mammalian brain contains neural stem/progenitor cells (NS/PCs) capable of generating new neurons, i.e., neurogenesis. Most drugs of abuse examined to date decrease adult hippocampal neurogenesis, but the effects of cannabis (marijuana or cannabinoids) on hippocampal neurogenesis remain unknown. This study aimed at investigating the potential regulatory capacity of the potent synthetic cannabinoid HU210 on hippocampal neurogenesis and its possible correlation with behavioral change.

    The recent discovery that the hippocampus is able to generate new neurons (i.e., neurogenesis) throughout the lifespan of mammals, including humans, has changed the way we think about the mechanisms of psychiatric disorders (12) and drug addiction (13). The subgranular zone of the dentate gyrus (SGZ) in the adult brain contains neural stem/progenitor cells (NS/PCs) capable of producing thousands of new granule cells per day (14). We, and others, have shown that these newborn hippocampal neurons are functionally integrated into the existing neuroanatomical circuitry (15, 16) and are positively correlated with hippocampus-dependent learning and memory processes (17) and the developmental mechanisms of stress and mood disorders (12). Recent studies have further shown that chronic fluoxetine treatment produced antidepressant and anxiolytic effects (18, 19) and the anxiolytic effects are likely achieved by promoting hippocampal neurogenesis (18).

    Although both HU210 and AEA exerted no significant effects on neuronal differentiation of NS/PCs, they significantly increased NS/PC proliferation, leading to increased total number of newborn neurons. Similar results were also obtained in freely moving adult rats. That is, chronic, but not acute, HU210 significantly increased the number of newborn hippocampal neurons in adult rats by promoting NS/PC proliferation but not differentiation. We also provided evidence indicating that the promoting effects of chronic HU210 treatment on adult hippocampal neurogenesis are not the outcome of hippocampal neuronal death, as we did not detect neuronal loss or dying hippocampal neurons following chronic HU210 injection. Overall, these data support the idea that cannabinoids are able to promote embryonic and adult hippocampal neurogenesis via the CB1 receptors in the NS/PCs.

    Following the observation that chronic HU210 treatment promoted neurogenesis in the dentate gyrus, we wondered whether chronic HU210–induced newborn neurons are of functional significance. Given the recent findings that chronic fluoxetine treatment produced antidepressant and anxiolytic effects (18, 19) and the anxiolytic effects are likely achieved by promoting hippocampal neurogenesis (18), we hypothesized that chronic HU210–induced hippocampal neurogenesis may also correlate with anxiolytic and antidepressant effects. Our subsequent experiments supported this hypothesis. After 1 month of chronic HU210 treatment, rats deprived of food for 48 hours showed significantly reduced latency to eat food in a novel environment, suggesting that chronic HU210 treatment exerted anxiolytic effects.

    One week after undergoing NSF testing, the same rats receiving chronic HU210 treatment showed a significantly reduced duration of immobility in the FST, indicating that chronic HU210 also exerts antidepressant effects. Because acute cannabinoid treatment profoundly affects motor function of humans and animals (1, 10), chronic HU210–induced shortened immobility in the FST may be produced by its action in changing the motor activity of rats. This is unlikely, however, as we observed no significant difference in the number of rats climbing (41, 42) among HU210-, AM281-, and vehicle-treated groups in the first 5 minutes of the pretest sessions of the FST. The anxiolytic- and antidepressant-like behavioral changes in rats 1 month after chronic HU210 treatment are unlikely to have been produced by the cannabinoid withdrawal effects, since, as shown in our recent study (8), rodents receiving chronic cannabinoid would display detectable cannabinoid withdrawal syndrome only after administration of CB1 receptor antagonists.

    Finally, the same rats with reduced measures of anxiety and depression following chronic HU210 treatment showed significantly increased numbers of BrdU-labeled cells within the dentate granule cell layer. These overall results thus confirmed our above-described novel findings that chronic HU210 treatment significantly increased newborn neurons in the hippocampal dentate gyrus (Figure 6).

    In summary, since adult hippocampal neurogenesis is suppressed following chronic administration of opiates (20), alcohol (21), nicotine (22), and cocaine (23), the present study suggests that cannabinoids are the only illicit drug that can promote adult hippocampal neurogenesis following chronic administration. Increased hippocampal neurogenesis appears to underlie the mechanism of anxiolytic- and antidepressant-like effects produced by a high dose of chronic HU210 treatment. The opposing effects of high doses of acute and chronic cannabinoids, together with the anxiolytic-like effects caused by a low dose of cannabinoids, may finally explain discrepancies in the clinical study literature regarding the effects of cannabinoid on anxiety and depression.

    Summasummarum: Cannabis forstærker neurogenesis, hvilket kort sagt resulterer i forbedret hukommelse/indlæring og humør.

    Gør det nu lovligt…

Viser 13 kommentarer - 136 til 148 (af 148 i alt)
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  • #162

    Arkham
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    #159: almen medicin har en meget probabilistisk tilgang til kausalitet, dvs. et statistisk signifikant sammenfald mellem cannabisforbrug og psykosetilfælde vil blive taget som et (pseudo/induktivt) bevis for en egentlig sammenhæng, præcis som vi har set med almindelig tobaksrygning og lungecancer de seneste år.

    Den type hypotese jeg alluderer til i #158 kunne f.eks. være af negativ universal karakter – “hashrygning medfører ikke psykoser.” I så fald ville ét enkelt observeret tilfælde modbevise hypotesen, forudsat monokausalitet (langt fra tilfældet her, men leg med for eksemplets skyld).

    Alt det her tjener bare til at illustrere, at enkeltobservationer skam også har deres plads i naturvidenskaben, alt afhængig af arbejdsform og kontekst.

    #163

    goatchen
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    #162
    Way to repeat #157….

    luls!

    #164

    Arkham
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    #163:

    #157 omtaler social videnskab. Efter #159 var en præcision nødvendig.

    #165

    goatchen
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    #164
    Metode er nu gældende for mere end blot sociale videnskab….
    Men meh, irrelevant for debatten.

    luls!

    #166

    Arkham
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    Ja, men da metoderne er 100% forskellige felterne imellem siger det meget lidt om relevansen for naturvidenskab. Men du har ret i det sidste du skriver

    #167

    SmileyMan3
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    #Arkham: Jeg forstår hvad du mener, og du har ret.

    #168

    Wack
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    Ok gad ikke lige læse det hele igennem men, jeg har røget de sidste 5-6 år af mit liv og kan ingen forskel mærke på min indlæring om ikke andet bliver den bedre når jeg ryger en joint og laver hjemmesider, kan bedre koncentrere mig om en ting af gangen, derimod bliver jeg forstyrret imens, taber jeg tit fatningen.
    Jeg ser mere alkohol som den store synder i det moderne drug kapløb, f.eks. hvor mange mennesker der ryger hash tager i byen og banker tænderne ud på hinanden? Så at sige at hash er mucho skadeligt eller ej er vel op til den enkelte person, men come on gi os nu en chance! Jeg har hørt alle undskyldningerne for at hash er ulovligt og endnu mangler jeg stadigt at høre et ordentligt argument.. So bring on the flame!

    K.

    #169

    stekok
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    Forbud skader samfundet kollektivt, det er efterhånden slået fast.

    Blev hamp mm. lovligt, ville de potentielle skader være mere individuelle

    #170

    SkaFt
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    #169
    HAHA!
    Det eneste der er blevet slået fast, er din evindelige påståelighed.
    Stekok – Borgmester i imaginationland!

    Hvad bliver det næste?

    #171

    Lightbringer
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    0# næppe og det er alkohol heller ikke!

    #172

    Silan
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    Sorry for bump, men kom lige til at læse den færdig og måtte have dette med…

    Jeg citere lige lidt hurtigt – skæv, fra den flotte peer-reviwed artikel maulwafer smed på bordet:

    “Ghodse (1986) has suggested that regular heavy users of cannabis may suffer repeated short episodes of psychosis and effectively ‘maintain’ themselves in a chronic psychotic state. This is a possibility, but Hall et al (1994) note that it is difficult to distinguish between a chronic cannabis psychosis and the co-occurrence of an illness such as schizophrenia with continued cannabis use. There is however, no robust evidence that heavy cannabis use may lead to a psychotic illness which persists after abstinence (Thomas, 1993).”

    Ooog så et maulwafer quote:

    SmileyMan3 – Hash er farligt og kan fremkalde psykoser. Dine egne links peger på artikler der siger det i relativt utvetydige vendinger.

    Jeg har hverken læst hele artiklen eller kilderne, men overstående virker ret endegyldigt.

    #173

    Kimozabi
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    #169:
    Er det blevet slået fast i andet end dine indlæg i denne tråd? Jeg synes f.eks. forbuddet mod børneporno er en meget god ting.

    "You don't want to see me when I'm angry - because I back up my rage with facts and documented sources." - The Credible Hulk.

    #174

    Synonymet
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    #172: Der er heller ikke noget endegyldigt bevis for, at det IKKE forholder sig sådan, at hashpsykoser kan være permanente. Så skal vi ikke bare konkludere, at det kan være begge dele?

    Nu har jeg så en ven, der har fået en hashpsykose, der er pænt fucking permanent. Den kunne måske være forekommet uden hash, men den startede, da han var hammerskæv.

    For mig er det endegyldigt bevis, men det er svært at bevise det på en videnskabelig og uafviselig måde, og du kan selvfølgelig vælge at tro, at jeg er en løgner.

    Men jeg forstår ikke, hvorfor det manglende bevis for, at hashpsykoser er permanente, skulle antyde, at de ikke er det, når der også mangler bevis på, at de IKKE er permanente. Hvorfor vejer dit manglende bevis mere i denne kontekst end mit manglende bevis?

    Hellere komme galt afsted, end slet ikke komme afsted.

Viser 13 kommentarer - 136 til 148 (af 148 i alt)
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