Urine signal

Single-locus genetic differences between males can change the urine signal. Maturing female mice attained their first estrus sooner (at 29.9 days) when exposed to urine from males that were +/+ at the t-locus than with that from... 

Homer AJ, Weissburg MJ, Derby CD (2008) The olfactory pathway mediates sheltering behavior of Caribbean spiny lobsters, Panulirus argus, to conspecific urine signals. J Comp Physiol A 194 243-253... 

Karavanich C, Atema J (1998b) Olfactory recognition of urine signals in dominance fights between male lobster, Homarus americanus. Behaviour 135 719-730... 

Fig. 13.2 Photograph showing chemical communication during aggressive interaction of two male Astacus leptodactylus. Both males were blindfolded using opaque film wrapped around the eyestalks. Urine signals were visualized using Fluorescein dye injected into the heart (for methodology see Breithaupt and Eger 2002)...

What is Communicated by Urine Signals in Agonistic Interactions ... 

One approach is to prepare a sample blank using urine known to be free of quinine. The fluorescent signal for the sample blank is subtracted from the urine sample s measured fluorescence. 

Most potentiometric electrodes are selective for only the free, uncomplexed analyte and do not respond to complexed forms of the analyte. Solution conditions, therefore, must be carefully controlled if the purpose of the analysis is to determine the analyte s total concentration. On the other hand, this selectivity provides a significant advantage over other quantitative methods of analysis when it is necessary to determine the concentration of free ions. For example, calcium is present in urine both as free Ca + ions and as protein-bound Ca + ions. If a urine sample is analyzed by atomic absorption spectroscopy, the signal is proportional to the total concentration of Ca +, since both free and bound calcium are atomized. Analysis with a Ca + ISE, however, gives a signal that is a function of only free Ca + ions since the protein-bound ions cannot interact with the electrode s membrane. 

When the natural product source contains racemic mixtures (of isomeric forms), then clearly the assignment of signal value to either or both variants of a compound needs to be determined. Alterations in receptor detection of chirality can change sensitivity to the geometrically alternate compound over the range 101 to 106. Of the lactones passed into urine and deposited on tarsal hairs of Black-tailed deer (Odocoileus... 

Their conclusions were that the compound 3. 3,4-dehydro-ero-brevicomin (DB) was capable of inter- and intra-sexual activity (see Chap. 7), but only if present in the (R, / -configuration, while its partner compound 4., 2-sec-butyldihydrothiazole (BT), was probably racemised in situ. The DB signal is required in a correct stereochemical form but the thiazolines activity in urine is not affected by a particular chirality (Novotny et al., 1995). 

In rabbits, the as yet unidentified maternal signal during lactation has analogous properties in guiding the reliable orientation of suckling, mainly via MOS input (Hudson and Distel, 1986 Schaal et al., unpubl.). Minor fractions may still function as flag contributors, exemplified by the attractiveness of proestrous elephant urine. Male responses show that intact urine is conspicuously more attractive in comparison with the pure insect mammal pheromone (9.) presented in water (Rasmussen et al., 1996). 

Female urine [estrous signal(s)] => Male flehmen => mucus [OBP] uptake... 

Fig. 7.7 Discrimination by F. (a) of estrous, vs. non-estrous, urine frequency in feral goats (from O Brien, 1982) and (b) within social groups, species-differences in responsiveness of male antelopes to urinary and/or genital signals (from Hart and Hart, 1987).

Ultra-sound emissions typically occur when male rodents are exposed to female odours or altricial neonates to maternal sources (Whitney, 1974 Conely and Bell, 1978). Without the VNO, sexually inexperienced male mice do not utter emissions at ultra-high frequencies (UHF), whereas those with prior experience vocalise after VN-x, as discussed above (Chap. 5). Female mouse urine contains a unique UHF-eliciting component which is non-volatile but ephemeral (Sipos et al., 1995). The signal is degraded by oxidation and disappears within 15 to 18 hours of deposition. Direct contact with freshly voided urine must occur before males will vocalise (sexually experienced or inexperienced). At least one of the olfactory systems is needed for UHF to be elicited by fresh urine complete deafferentation abolishes the response (Sipos et al., 1993). Exposure to females permits UHF to be elicited by other than chemical cues (Labov and Wysocki, 1989). Nocturnal or cryptic species conceivably use ultrasound to advertise male presence whether this is to deter other males or assist with female location is unclear. 

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