The Company of Biologists

Table 5.

The rate of ⁵¹Cr-EDTA clearance from the haemolymph,extracellular fluid volume and body mass (% loss) of Gecarcoidea natalis during the 1997 dry season

	⁵¹Cr-EDTA clearance (ml kg⁻¹day⁻¹)			Extracellular fluid volume (% body mass)
Dry Season	Water	No water	Water	No water	Water	No water
Saline	130.02±12.10	90.57±4.88 ^†	19.15±0.76	19.00±0.85	3.61±0.74	3.70±0.91
Dopamine	123.44±5.62	93.25±5.84 ^†	22.94±1.69	20.05±0.92 ^†	3.24±0.83	3.60±0.78
db-cAMP	125.32±14.07	103.20±16.8 ^†	21.99±1.57	17.60±0.48 ^†	4.24±0.57	4.06±0.51
Serotonin	151.11±10.72 ^{^*}	108.72±13.36 ^{^*}, ^†	21.29±0.99	17.69±1.36	4.50±0.82	4.00±0.83
Octopamine	123.16±7.37	90.33±9.26 ^†	19.22±1.08	20.31±0.81	4.43±0.46	3.90±0.80

	⁵¹Cr-EDTA clearance (ml kg⁻¹day⁻¹)			Extracellular fluid volume (% body mass)
Dry Season	Water	No water	Water	No water	Water	No water
Saline	130.02±12.10	90.57±4.88 ^†	19.15±0.76	19.00±0.85	3.61±0.74	3.70±0.91
Dopamine	123.44±5.62	93.25±5.84 ^†	22.94±1.69	20.05±0.92 ^†	3.24±0.83	3.60±0.78
db-cAMP	125.32±14.07	103.20±16.8 ^†	21.99±1.57	17.60±0.48 ^†	4.24±0.57	4.06±0.51
Serotonin	151.11±10.72 ^{^*}	108.72±13.36 ^{^*}, ^†	21.29±0.99	17.69±1.36	4.50±0.82	4.00±0.83
Octopamine	123.16±7.37	90.33±9.26 ^†	19.22±1.08	20.31±0.81	4.43±0.46	3.90±0.80

The crabs were treated by infusion of saline, dopamine, serotonin,octopamine (all at 10⁻¹⁰ mol g⁻¹) or db-cAMP(10⁻⁹ mol g⁻¹). Infusions in saline carrier at 1 μ1 g⁻¹ were performed at 8 h intervals for 3 days. Crabs were held within enclosures that were open at the top and allowed crabs contact with the forest floor. Values are means ± s.e.m.(N=12 in each group).

, effect of drug;

†

, effect of removing drinking water. Extracellular fluid volume was measured from EDTA space, expressed as % body mass. The change in % body mass was tested by ANOVA of the arcsin-transformed values; there were no significant differences between the values.

View Large

This Feature Is Available To Subscribers Only