Response of dermal melanophores to epinephrine after removal of the epidermal barrier

Adrenoceptors in cryptic patterning of a flatfish, Pleuronectes americanus

“…However, the epidermis is considered a serious barrier (to free access of exogenous chemicals) to melanophores of scale slips (Spaeth 1913) and other skin preparations (Fernando & Grove 1974a, b )e xplaining, at least in part, the relatively high concentrations used. Goldfish display an apparent tenfold increase in sensitivity to adrenaline after epidermal removal from scale slips (Stone & Chavin 1974), although the current work indicates that removal of this barrier can have an even greater apparent effect around the threshold con centration. Also, the faster melanosome aggregation without the epidermis is further evidence of this barrier against diffusion.…”

“…All scale slips in individual experiments were treated alike and replicates gave no indication of catecholamine oxidation. In two experiments the epidermis was removed by incubation with 1% EDTA (ethylenediaminetetraacetic acid), 0.44% N aH C 0 3 and 0.4% NaCl (Stone & Chavin 1974) at pH 7.8 kept on ice for 30 min to 2 h with gentle stirring, before scale slips were immersed in bss.…”

Adrenoceptors in cryptic patterning of a flatfish, Pleuronectes americanus

“…However, the epidermis is considered a serious barrier (to free access of exogenous chemicals) to melanophores of scale slips (Spaeth 1913) and other skin preparations (Fernando & Grove 1974a, b )e xplaining, at least in part, the relatively high concentrations used. Goldfish display an apparent tenfold increase in sensitivity to adrenaline after epidermal removal from scale slips (Stone & Chavin 1974), although the current work indicates that removal of this barrier can have an even greater apparent effect around the threshold con centration. Also, the faster melanosome aggregation without the epidermis is further evidence of this barrier against diffusion.…”

“…All scale slips in individual experiments were treated alike and replicates gave no indication of catecholamine oxidation. In two experiments the epidermis was removed by incubation with 1% EDTA (ethylenediaminetetraacetic acid), 0.44% N aH C 0 3 and 0.4% NaCl (Stone & Chavin 1974) at pH 7.8 kept on ice for 30 min to 2 h with gentle stirring, before scale slips were immersed in bss.…”

Sensitivity of winter flounder melanophores after removal of the epidermis from in vitro preparations

“…The melanosome aggregating effect of K + after removal of the epidermis demonstrates that the scale-slip nerve terminals are still functional after this treatment. Although microscopic examination can be used to determine whether separation of the epidermis has been accomplished efficiently with minimum dermal damage, cell viability after this treatment is difficult to demonstrate and evaluate (Stone & Chavin, 1974). These authors used the pigment aggregating response of the melanophores to adrenaline and dispersion with Na + as an index of damage to this dermal cell population.…”

“…6H 2 O, 0·64; CaCl 2 , 1·53; glucose, 5·6. The epidermis was removed in a solution of 1% EDTA, 0·44% NaHCO 3 and 0·4% NaCl (Stone & Chavin, 1974) at pH 7·8 in a beaker kept on ice. For 30 min to 2 h the EDTA solution (temperature 7 1 C) and scale slips were stirred gently until peeling of the epidermis was observed, and confirmed microscopically by the disappearance of the epidermal melanophores and improved clarity of the dermal melanophores.…”

The relative in vitro responsiveness of melanophores of winter flounder to α‐MSH and MCH

“…During experiments, flounder were kept in individual black Plexiglas aquaria (400 mm 225 mm 203 mm) supplied with running sea water at ambient temperature and under seasonal photoperiod with 60 W incandescent illumination c. 1 m above the tanks. Scale slips were plucked from each pattern component and the epidermis removed in a solution of 1% ethylenediaminetetraacetic acid (EDTA), 0·44% NaHCO 3 and 0·4% NaCl (Stone & Chavin, 1974) at pH 7·8 in a beaker kept on ice. For 30 min to 2 h the EDTA solution, with the scale slips, was stirred gently until peeling of the epidermis was observed and confirmed microscopically by the disappearance of the epidermal melanophores and by the improved clarity of the dermal melanophores.…”

Adrenoceptors in cryptic patterning of a flatfish, Pleuronectes americanus

“…However, the epidermis is considered a serious barrier (to free access of exogenous chemicals) to melanophores of scale slips (Spaeth 1913) and other skin preparations (Fernando & Grove 1974a, b )e xplaining, at least in part, the relatively high concentrations used. Goldfish display an apparent tenfold increase in sensitivity to adrenaline after epidermal removal from scale slips (Stone & Chavin 1974), although the current work indicates that removal of this barrier can have an even greater apparent effect around the threshold con centration. Also, the faster melanosome aggregation without the epidermis is further evidence of this barrier against diffusion.…”

“…All scale slips in individual experiments were treated alike and replicates gave no indication of catecholamine oxidation. In two experiments the epidermis was removed by incubation with 1% EDTA (ethylenediaminetetraacetic acid), 0.44% N aH C 0 3 and 0.4% NaCl (Stone & Chavin 1974) at pH 7.8 kept on ice for 30 min to 2 h with gentle stirring, before scale slips were immersed in bss.…”

Sensitivity of winter flounder melanophores after removal of the epidermis from in vitro preparations

“…The melanosome aggregating effect of K + after removal of the epidermis demonstrates that the scale-slip nerve terminals are still functional after this treatment. Although microscopic examination can be used to determine whether separation of the epidermis has been accomplished efficiently with minimum dermal damage, cell viability after this treatment is difficult to demonstrate and evaluate (Stone & Chavin, 1974). These authors used the pigment aggregating response of the melanophores to adrenaline and dispersion with Na + as an index of damage to this dermal cell population.…”

“…6H 2 O, 0·64; CaCl 2 , 1·53; glucose, 5·6. The epidermis was removed in a solution of 1% EDTA, 0·44% NaHCO 3 and 0·4% NaCl (Stone & Chavin, 1974) at pH 7·8 in a beaker kept on ice. For 30 min to 2 h the EDTA solution (temperature 7 1 C) and scale slips were stirred gently until peeling of the epidermis was observed, and confirmed microscopically by the disappearance of the epidermal melanophores and improved clarity of the dermal melanophores.…”

The relative in vitro responsiveness of melanophores of winter flounder to α‐MSH and MCH

“…During experiments, flounder were kept in individual black Plexiglas aquaria (400 mm 225 mm 203 mm) supplied with running sea water at ambient temperature and under seasonal photoperiod with 60 W incandescent illumination c. 1 m above the tanks. Scale slips were plucked from each pattern component and the epidermis removed in a solution of 1% ethylenediaminetetraacetic acid (EDTA), 0·44% NaHCO 3 and 0·4% NaCl (Stone & Chavin, 1974) at pH 7·8 in a beaker kept on ice. For 30 min to 2 h the EDTA solution, with the scale slips, was stirred gently until peeling of the epidermis was observed and confirmed microscopically by the disappearance of the epidermal melanophores and by the improved clarity of the dermal melanophores.…”

Adrenoceptors in cryptic patterning of a flatfish, Pleuronectes americanus

“…However, the epidermis is considered a serious barrier (to free access of exogenous chemicals) to melanophores of scale slips (Spaeth 1913) and other skin preparations (Fernando & Grove 1974a, b )e xplaining, at least in part, the relatively high concentrations used. Goldfish display an apparent tenfold increase in sensitivity to adrenaline after epidermal removal from scale slips (Stone & Chavin 1974), although the current work indicates that removal of this barrier can have an even greater apparent effect around the threshold con centration. Also, the faster melanosome aggregation without the epidermis is further evidence of this barrier against diffusion.…”

“…All scale slips in individual experiments were treated alike and replicates gave no indication of catecholamine oxidation. In two experiments the epidermis was removed by incubation with 1% EDTA (ethylenediaminetetraacetic acid), 0.44% N aH C 0 3 and 0.4% NaCl (Stone & Chavin 1974) at pH 7.8 kept on ice for 30 min to 2 h with gentle stirring, before scale slips were immersed in bss.…”

Sensitivity of winter flounder melanophores after removal of the epidermis from in vitro preparations

“…The melanosome aggregating effect of K + after removal of the epidermis demonstrates that the scale-slip nerve terminals are still functional after this treatment. Although microscopic examination can be used to determine whether separation of the epidermis has been accomplished efficiently with minimum dermal damage, cell viability after this treatment is difficult to demonstrate and evaluate (Stone & Chavin, 1974). These authors used the pigment aggregating response of the melanophores to adrenaline and dispersion with Na + as an index of damage to this dermal cell population.…”

“…6H 2 O, 0·64; CaCl 2 , 1·53; glucose, 5·6. The epidermis was removed in a solution of 1% EDTA, 0·44% NaHCO 3 and 0·4% NaCl (Stone & Chavin, 1974) at pH 7·8 in a beaker kept on ice. For 30 min to 2 h the EDTA solution (temperature 7 1 C) and scale slips were stirred gently until peeling of the epidermis was observed, and confirmed microscopically by the disappearance of the epidermal melanophores and improved clarity of the dermal melanophores.…”

The relative in vitro responsiveness of melanophores of winter flounder to α‐MSH and MCH

“…During experiments, flounder were kept in individual black Plexiglas aquaria (400 mm 225 mm 203 mm) supplied with running sea water at ambient temperature and under seasonal photoperiod with 60 W incandescent illumination c. 1 m above the tanks. Scale slips were plucked from each pattern component and the epidermis removed in a solution of 1% ethylenediaminetetraacetic acid (EDTA), 0·44% NaHCO 3 and 0·4% NaCl (Stone & Chavin, 1974) at pH 7·8 in a beaker kept on ice. For 30 min to 2 h the EDTA solution, with the scale slips, was stirred gently until peeling of the epidermis was observed and confirmed microscopically by the disappearance of the epidermal melanophores and by the improved clarity of the dermal melanophores.…”