2,3,7,8-Tetrachlorodibenzo-p-dioxin enhances responsiveness to post-ingestive satiety signals

Assessment by c‐Fos Immunostaining of Changes in Brain Neural Activity Induced by 2,3,7,8‐Tetrachlorodibenzo‐p‐Dioxin (TCDD) and Leptin in Rats*

“…Several studies support the notion that altered central regulation of energy homeostasis and body weight underlies the syndrome (Seefeld et al 1984; Pohjanvirta & Tuomisto 1990; Pohjanvirta et al 1990a & 1991). Wasting is not due to gross malabsorption or diarrhoea, nor does it seem to be attributable to nausea (Pohjanvirta et al 1994), but the animals appear to pursue a lower body weight level by adjusting their food intake accordingly (Seefeld et al 1984; Pohjanvirta & Tuomisto 1990). Even after a high sublethal dose, treated animals retain and defend a lowered body weight level (Seefeld et al 1984; Tuomisto et al 1995 & 1999a).…”

“…TCDD is the most potent congener in the group of dioxins. It is the most potent anorexigen known, but the mechanism by which it exerts its drastic effect on food intake is obscure (Pohjanvirta & Tuomisto 1990; Tuomisto et al 1995; & 2000). Therefore, we set out the present study to examine whether TCDD might activate or deactivate those hypothalamic nuclei previously established to be involved in the control of feeding behaviour.…”

Assessment by c‐Fos Immunostaining of Changes in Brain Neural Activity Induced by 2,3,7,8‐Tetrachlorodibenzo‐p‐Dioxin (TCDD) and Leptin in Rats*

“…Several studies support the notion that altered central regulation of energy homeostasis and body weight underlies the syndrome (Seefeld et al 1984; Pohjanvirta & Tuomisto 1990; Pohjanvirta et al 1990a & 1991). Wasting is not due to gross malabsorption or diarrhoea, nor does it seem to be attributable to nausea (Pohjanvirta et al 1994), but the animals appear to pursue a lower body weight level by adjusting their food intake accordingly (Seefeld et al 1984; Pohjanvirta & Tuomisto 1990). Even after a high sublethal dose, treated animals retain and defend a lowered body weight level (Seefeld et al 1984; Tuomisto et al 1995 & 1999a).…”

“…TCDD is the most potent congener in the group of dioxins. It is the most potent anorexigen known, but the mechanism by which it exerts its drastic effect on food intake is obscure (Pohjanvirta & Tuomisto 1990; Tuomisto et al 1995; & 2000). Therefore, we set out the present study to examine whether TCDD might activate or deactivate those hypothalamic nuclei previously established to be involved in the control of feeding behaviour.…”

Mechanisms of circadian clock interactions with aryl hydrocarbon receptor signalling

“…Rhythms of clock gene transcripts, specifically Per1 and Bmal1 , and the PER1 proteins are also perturbed in the SCN of TCDD‐exposed mice (Mukai et al., ). Similarly, large doses of TCDD alter the timing of food intake, such that 50% of the daily food consumption occurs during the early morning in nocturnal rats (Pohjanvirta & Tuomisto, ). Unfortunately, that study did not explore locomotor activity, which may account for the changes in feeding.…”

Role of Aryl Hydrocarbon Receptor in Circadian Clock Disruption and Metabolic Dysfunction

“…43,44 AhR activation in mice and hamsters alters rhythms of feeding and activity, gene expression, and the hormones prolactin, corticosterone, and melatonin. [45][46][47][48][49][50][51] Human exposure to pesticides, which contain potent AhR agonists, increases the risk for idiopathic rapid eye movement sleep behavior disorder, further establishing a link between AhR, sleep, and circadian rhythms. 52 Since AhR and Arnt are expressed within hypothalamic nuclei that regulate circadian rhythmicity, feeding behavior, and hormone secretion, and AhR activation alters gene expression in the hypothalamus, AhR-dependent mechanisms should be further explored.…”

“…52 Since AhR and Arnt are expressed within hypothalamic nuclei that regulate circadian rhythmicity, feeding behavior, and hormone secretion, and AhR activation alters gene expression in the hypothalamus, AhR-dependent mechanisms should be further explored. 41,42,48,50 Activation of AhR alters the expression patterns of circadian clock genes and suppresses circadian rhythms. Reciprocally, genetic alteration of the circadian clock influences AhR signaling and sensitivity to agonist-induced activation of AhR and AhR target genes.…”

Assessment by c‐Fos Immunostaining of Changes in Brain Neural Activity Induced by 2,3,7,8‐Tetrachlorodibenzo‐p‐Dioxin (TCDD) and Leptin in Rats*

“…Several studies support the notion that altered central regulation of energy homeostasis and body weight underlies the syndrome (Seefeld et al 1984; Pohjanvirta & Tuomisto 1990; Pohjanvirta et al 1990a & 1991). Wasting is not due to gross malabsorption or diarrhoea, nor does it seem to be attributable to nausea (Pohjanvirta et al 1994), but the animals appear to pursue a lower body weight level by adjusting their food intake accordingly (Seefeld et al 1984; Pohjanvirta & Tuomisto 1990). Even after a high sublethal dose, treated animals retain and defend a lowered body weight level (Seefeld et al 1984; Tuomisto et al 1995 & 1999a).…”

“…TCDD is the most potent congener in the group of dioxins. It is the most potent anorexigen known, but the mechanism by which it exerts its drastic effect on food intake is obscure (Pohjanvirta & Tuomisto 1990; Tuomisto et al 1995; & 2000). Therefore, we set out the present study to examine whether TCDD might activate or deactivate those hypothalamic nuclei previously established to be involved in the control of feeding behaviour.…”

Mechanisms of circadian clock interactions with aryl hydrocarbon receptor signalling

“…Rhythms of clock gene transcripts, specifically Per1 and Bmal1 , and the PER1 proteins are also perturbed in the SCN of TCDD‐exposed mice (Mukai et al., ). Similarly, large doses of TCDD alter the timing of food intake, such that 50% of the daily food consumption occurs during the early morning in nocturnal rats (Pohjanvirta & Tuomisto, ). Unfortunately, that study did not explore locomotor activity, which may account for the changes in feeding.…”

Role of Aryl Hydrocarbon Receptor in Circadian Clock Disruption and Metabolic Dysfunction

“…43,44 AhR activation in mice and hamsters alters rhythms of feeding and activity, gene expression, and the hormones prolactin, corticosterone, and melatonin. [45][46][47][48][49][50][51] Human exposure to pesticides, which contain potent AhR agonists, increases the risk for idiopathic rapid eye movement sleep behavior disorder, further establishing a link between AhR, sleep, and circadian rhythms. 52 Since AhR and Arnt are expressed within hypothalamic nuclei that regulate circadian rhythmicity, feeding behavior, and hormone secretion, and AhR activation alters gene expression in the hypothalamus, AhR-dependent mechanisms should be further explored.…”

“…52 Since AhR and Arnt are expressed within hypothalamic nuclei that regulate circadian rhythmicity, feeding behavior, and hormone secretion, and AhR activation alters gene expression in the hypothalamus, AhR-dependent mechanisms should be further explored. 41,42,48,50 Activation of AhR alters the expression patterns of circadian clock genes and suppresses circadian rhythms. Reciprocally, genetic alteration of the circadian clock influences AhR signaling and sensitivity to agonist-induced activation of AhR and AhR target genes.…”

Assessment by c‐Fos Immunostaining of Changes in Brain Neural Activity Induced by 2,3,7,8‐Tetrachlorodibenzo‐p‐Dioxin (TCDD) and Leptin in Rats*

“…Several studies support the notion that altered central regulation of energy homeostasis and body weight underlies the syndrome (Seefeld et al 1984; Pohjanvirta & Tuomisto 1990; Pohjanvirta et al 1990a & 1991). Wasting is not due to gross malabsorption or diarrhoea, nor does it seem to be attributable to nausea (Pohjanvirta et al 1994), but the animals appear to pursue a lower body weight level by adjusting their food intake accordingly (Seefeld et al 1984; Pohjanvirta & Tuomisto 1990). Even after a high sublethal dose, treated animals retain and defend a lowered body weight level (Seefeld et al 1984; Tuomisto et al 1995 & 1999a).…”

“…TCDD is the most potent congener in the group of dioxins. It is the most potent anorexigen known, but the mechanism by which it exerts its drastic effect on food intake is obscure (Pohjanvirta & Tuomisto 1990; Tuomisto et al 1995; & 2000). Therefore, we set out the present study to examine whether TCDD might activate or deactivate those hypothalamic nuclei previously established to be involved in the control of feeding behaviour.…”

Mechanisms of circadian clock interactions with aryl hydrocarbon receptor signalling

“…Rhythms of clock gene transcripts, specifically Per1 and Bmal1 , and the PER1 proteins are also perturbed in the SCN of TCDD‐exposed mice (Mukai et al., ). Similarly, large doses of TCDD alter the timing of food intake, such that 50% of the daily food consumption occurs during the early morning in nocturnal rats (Pohjanvirta & Tuomisto, ). Unfortunately, that study did not explore locomotor activity, which may account for the changes in feeding.…”

Role of Aryl Hydrocarbon Receptor in Circadian Clock Disruption and Metabolic Dysfunction

“…43,44 AhR activation in mice and hamsters alters rhythms of feeding and activity, gene expression, and the hormones prolactin, corticosterone, and melatonin. [45][46][47][48][49][50][51] Human exposure to pesticides, which contain potent AhR agonists, increases the risk for idiopathic rapid eye movement sleep behavior disorder, further establishing a link between AhR, sleep, and circadian rhythms. 52 Since AhR and Arnt are expressed within hypothalamic nuclei that regulate circadian rhythmicity, feeding behavior, and hormone secretion, and AhR activation alters gene expression in the hypothalamus, AhR-dependent mechanisms should be further explored.…”

“…52 Since AhR and Arnt are expressed within hypothalamic nuclei that regulate circadian rhythmicity, feeding behavior, and hormone secretion, and AhR activation alters gene expression in the hypothalamus, AhR-dependent mechanisms should be further explored. 41,42,48,50 Activation of AhR alters the expression patterns of circadian clock genes and suppresses circadian rhythms. Reciprocally, genetic alteration of the circadian clock influences AhR signaling and sensitivity to agonist-induced activation of AhR and AhR target genes.…”