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1. 5-Hydroxytryptamine (5-HT) stimulates fluid secretion by semi-isolated Malpighian tubules of Locusta in a dose-dependent manner. 2. The threshold of stimulation is between 10−8 and 10−7 M 5-HT; maximal activation occurs at doses greater than 10−6 M. 3. Relative to the activation induced by diuretic hormone (storage lobe extracts), 5-HT increases the rate of fluid secretion by only 65%. 4. Phentolamine, the α-adrenergic blocker, failed to inhibit either DH or 5-HT stimulated secretion. 5. Diuretic hormone raises the levels of intracellular of cAMP, and activates adenylate cyclase in plasma membrane preparations of Locusta Malpighian tubules. 6. 5-HT (10−4 M) has no effect in either assay system. 7. Thus 5-HT can stimulate fluid secretion independently of cAMP. 8. A hypothetical model for hormone stimulated fluid secretion by Locusta Malpighian tubules, involving dual-receptor activation, is proposed. 9. Other biogenic amines, including octopamine, adrenalin, dopamine, synephrine and the formamidine chlordimeform were tested for their ability to stimulate fluid secretion. 10. Only dopamine showed a weakly stimulatory effect.

The global financial crisis of 2007-2009 exposed flaws and shortcomings in the global economic architecture, and has sparked an international debate about possible remedies for them. The postwar global architecture was essentially guided by the major developed economies, and was centered around the IMF, the GATT – the predecessor of the WTO – and the World Bank. Today, however, the balance of economic and financial power is shifting toward the emerging economies, especially those in Asia, and both global governance and economic policy thinking are beginning to reflect this shift. This book addresses the important question of how a regional architecture, particularly one in Asia, can induce a supply of regional public goods that can complement and strengthen the global public goods supplied through the global architecture. These public goods include institutions to help maintain financial stability, support more open trading regimes and promote sustainable economic development.

To define the hormonal influences that are directly involved in the hair follicle cycles of animals with differing patterns of fibre growth and moulting, we have investigated the possible presence of IGF-I and melatonin receptors on the dermis and hair follicles of cashmere and Angora goats, sampled in February, March and June, using quantitative in vitro autoradiography. The presence of IGF-I receptors in the dermis of both breeds of goat was determined using cryostat sections incubated with 50 pm 125I-labelled IGF-I in the presence or absence of 50 nm IGF-I. Sections of the growing tip of deer antlers containing the cartilaginous zone, a tissue known to contain high concentrations of specific IGF-I receptors, were used as a positive control. As the production of antler velvet uniquely involves the generation of hair follicles de novo, the presence of IGF-I receptors in the velvet-producing region was also investigated. In both breeds of goat, specific 125I-IGF-I binding was localised over the inner and outer root sheath, the matrix, the germinal matrix, the dermal papilla and the sebaceous glands and satisfied the basic kinetic criteria considered to be representative of a specific IGF-I receptor. Analysis of saturation isotherms using a one-site binding model revealed dissociation constants (Kd) in the range 0·1–0·9 nm and theoretical maximal numbers of binding sites (Bmax) between 21·4 and 45·6 fmol/mg tissue. Kd and Bmax values derived from cashmere and Angora goats sampled at different times of the year did not differ significantly between breeds or sampling times. Specific 125I-IGF-I binding was also localised to the developing follicles on the deer antler dermis. The presence of melatonin receptors within the goat dermis was also investigated. Sections were incubated with 100 pm 2-[125I]iodomelatonin with or without 0·1 μm melatonin, along with sections of sheep pars tuberalis which are known to contain high levels of high-affinity melatonin receptors. No displaceable 2-[125I]iodomelatonin binding was found on any sections of the cashmere or Angora skin analysed. It is therefore concluded that melatonin receptors are not present on the hair follicles or associated structures. IGF-I receptors are present on the hair follicle and sebaceous gland and may be involved in the growth of both seasonally and non-seasonally produced fibre and in the development of antler velvet. Journal of Endocrinology (1996) 151, 55–63

Melatonin receptors belong to the superfamily of G protein-coupled receptors. Cloning of Mel1c receptors expressed in Xenopus skin revealed the existence of a polymorphism for these receptors. Heterologous expression of the two allelic isoforms, called Mel1c(alpha) and Mel1c(beta), indicated functional differences in their signalling properties. Both isoforms are coupled to the cAMP and cGMP pathways. However, the alpha isoform is preferentially coupled to the cAMP pathway, whereas the beta isoform couples preferentially to the cGMP pathway. Coupling differences may be explained by the fact that five of the six amino acid substitutions between the two isoforms are localized within intracellular receptor regions potentially involved in G protein coupling. Allelic isoforms were also observed for Mel1a receptors expressed in ovine pars tuberalis, suggesting that polymorphism is a general feature of the melatonin receptor family. We also evaluated the potential of the two human melatonin receptor subtypes, Mel1a and Mel1b, to modulate the cGMP pathway. Melatonin inhibited intracellular cGMP levels in a dose-dependent manner in HEK293 cells transfected with the human Mel1b receptor. This was not the case for HEK293 cells transfected with the human Mel1a receptor. In conclusion, our results indicate that the expression of receptor subtypes and isoforms may permit differential signalling between melatonin receptors.

In light of the experience of the global financial crisis, this book develops concrete recommendations for financial sector reform and regulation in Asian economies aimed at preventing the recurrence of systemic financial crises, improving the ability to manage and resolve crises, managing capital flows and promoting the development of Asian bond markets.

This book makes concrete macroeconomic policy recommendations for Asian economies aimed at minimizing the impacts of an economic and financial downturn, and setting the stage for an early return to sustainable growth. The focus is on short-term measures related to the cycle. The three main areas addressed are: monetary policy measures to achieve both macroeconomic and financial stability; exchange rate policy and foreign exchange reserve management, including the potential for regional exchange rate cooperation; and ways to ease the constraints on policy resulting from the so-called ‘impossible trinity’ of fixed exchange rates, open capital accounts and independent monetary policy.

The global financial crisis of 2007-2009 exposed flaws and shortcomings in the global economic architecture, and has sparked an international debate about possible remedies for them. The postwar global architecture was essentially guided by the major developed economies, and was centered around the IMF, the GATT – the predecessor of the WTO – and the World Bank. Today, however, the balance of economic and financial power is shifting toward the emerging economies, especially those in Asia, and both global governance and economic policy thinking are beginning to reflect this shift. This book addresses the important question of how a regional architecture, particularly one in Asia, can induce a supply of regional public goods that can complement and strengthen the global public goods supplied through the global architecture. These public goods include institutions to help maintain financial stability, support more open trading regimes and promote sustainable economic development.

Siberian hamsters decreased body weight by 30% during 18 wk in short day (SD) vs. long day (LD) controls. Subsequent imposed food deprivation (FD; 24 h) caused a further 10% decrease. In the hypothalamic arcuate nucleus (ARC), SDs reduced proopiomelanocortin (POMC) gene expression and agouti-related protein (AGRP) mRNA was elevated, changes that summate to reduced catabolic drive through the melanocortin receptors. There was no effect of photoperiod on neuropeptide Y (NPY), melanin concentrating hormone, orexin, or corticotropin-releasing factor mRNAs. Superimposed FD increased AGRP gene expression and caused a localized elevation of NPY mRNA in the ARC. Both adipose tissue leptin and ARC leptin receptor (OB-Rb) mRNAs were downregulated in SDs, whereas FD increased OB-Rb gene expression. Thus OB-Rb mRNA is differentially regulated by acute and chronic changes in plasma leptin in this species. In a separate experiment in LDs, AGRP gene expression was increased by 24 or 48 h FD, whereas POMC mRNA was downregulated in the caudal ARC. AGRP and NPY mRNAs were extensively coexpressed in the ARC, and their differential regulation by photoperiod and FD is suggestive of transcript-specific regulation at the level of individual neurons.

Given the current state of technology, the existing resource supplies, and environmental constraints, we examine how much shale oil could be profitably produced in the Western United States, what processes would be used, and which constraints would be binding in long-run equilibrium. Using an activity analysis model, we show that production of over 15 million barrels of shale oil per day (five-sixths of present U.S. oil consumption) is a profitable activity when the price of oil is $18 per barrel (1975 dollars). In testing the sensitivity of our results, we find that, even under quite conservative assumptions, production of two million barrels per day is economically feasible in the long run when the selling price of oil exceeds $12 per barrel.