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Suchandra Ghosh

Bio: Suchandra Ghosh is an academic researcher from University of Calcutta. The author has contributed to research in topics: Opioidergic & Bicuculline. The author has an hindex of 4, co-authored 13 publications receiving 43 citations.

Papers
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Journal ArticleDOI
TL;DR: There is an involvement of serotonergic regulation in the opioidergic-cholinergic interaction via GABA system in HET-induced increase in BT and it may be concluded that HET exposure activates the cholinergic system through the activation of opioiderGic and Serotonergic system and hence increased the BT.
Abstract: Exposure (2 h) of adult male albino rats to higher environmental temperature (HET, 40 degrees C) significantly increased body temperature (BT). Administration of (a) 5-HTP (5 mg/kg, i.p.) or morphine (1 mg/kg, i.p.) or physostigmine (0.2 mg/kg, i.p.) alone significantly increased and (b) methysergide (1 mg/kg, i.p.) or naloxone (1 mg/kg, i.p.) or atropine (5 mg/kg, i.p.) reduced the BT of both normal and HET exposed rats. Further, it was observed that morphine prevented the methysergide-induced hypothermia and 5-HTP potentiated the morphine-induced hyperthermia in both normal and HET exposed conditions. Biochemical study also indicates that serotonin metabolism was increased but GABA utilization was reduced following exposure to HET.5-HTP or bicuculline-induced hyperthermia in control and HET exposed rat was potentiated with the coadministration of bicuculline and 5-HTP. The cotreatment of bicuculline with methysergide prevented the methysergide-induced attenuation of BT of heat exposed rat, rather BT was significantly enhanced indicating that inhibition of GABA system under heat exposed condition may activate the serotonergic activity. Further (a) enhancement of (i) morphine-induced hyperthermia with physostigmine (ii) physostigmine- or morphine+physostigmine-induced increase of BT with 5-HTP and (b) reduction of (i) morphine- or morphine + 5-HTP-induced hyperthermia with atropine and (ii) atropine-induced hypothermia with 5-HTP in both normal and HET exposed conditions suggest that HET exposure activates the cholinergic system through the activation of opioidergic and serotonergic system and hence increased the BT. Thus, it may be concluded that there is an involvement of serotonergic regulation in the opioidergic-cholinergic interaction via GABA system in HET-induced increase in BT.

11 citations

Journal ArticleDOI
TL;DR: The results suggest that short-term exposure to HET activates the opioidergic neuron, which activates cholinergic activity through the inhibition of GABAergic system and, thus, enhances the BT.
Abstract: Exposure (2 h) of male albino rats to higher environmental temperature (HET, 40 °C) significantly increased the body temperature (BT). Administration of bicuculline (1 mg/kg, IP), physostigmine (0.2 mg/kg, IP), or their combination significantly raised the BT of normal rats (kept at 28 °C) or of HET-exposed rats. Atropine (5 mg/kg, IP) abolished the hyperthermic effect of bicuculline in normal and HET-exposed rats. The BT of normal and HET-exposed rat was increased with morphine (1 mg/kg, IP) and was reduced with naloxone (1 mg/kg, IP). Bicuculline or physostigmine-induced rise in BT of HET-exposed rats was potentiated following cotreatment of physostigmine with morphine. Atropine-induced hypothermia was abolished due to the cotreatment of atropine with morphine in HET-exposed rats. Further, (morphine + bicuculline)-induced hyperthermia in HET-exposed rats was potentiated with physostigmine but was attenuated with atropine. In normal rats (kept at 28 °C), only atropine attenuated (morphine + bicuculline)-induced hyperthermia. l -Dopa + carbidopa or haloperidol did not significantly affect the BT of rats under similar conditions. These results suggest that short-term (2 h) exposure to HET activates the opioidergic neuron, which activates cholinergic activity through the inhibition of GABAergic system and, thus, enhances the BT.

7 citations

Journal ArticleDOI
TL;DR: The importance of the Andhra cote de l’Andhra au sein du reseau de commerce maritime du Golfe du Bengale is discussed in this article, where the author et al. etudie l'importance of la cote of l'Andhra and the importance of its ports.
Abstract: L’A. etudie l’importance de la cote de l’Andhra au sein du reseau de commerce maritime du Golfe du Bengale. Il s’appuie, d’une part, sur les temoignages epigraphiques telle l’inscription de Ghantasala, avec une attention particuliere portee au terme « Mahānāvika » (capitaine de navire); d’autre part, sur les complements apportes par la numismatique et les sources litteraires (notamment en ce qui concerne le contexte et la prosperite de l’arriere pays pour assurer la richesse des ports).

7 citations

Journal ArticleDOI
TL;DR: In this paper, the boundary representations of copper-plate charters issued by three dynasties of Assam were studied. But the boundary representation of the charters was not described in detail.
Abstract: Taking cue from B.D. Chatopadhyaya’s seminal study on boundary markers to understand the spatial characteristics of rural settlements, a study on the boundary representations of copper-plate charters issued by three dynasties of Assam was undertaken. A close reading of the charters indicates that there was a significant variation in the pattern of delineating the boundaries. While limited boundary specifications could be seen in the copperplates of the Varmans, the Śālasthambhas initially set a pattern of describing eight boundaries of their donated lands by categorically mentioning the number eight but gradually this was overlooked. The Pālas of Kāmarūpa, on the other hand, were inclined to give much more detailed boundary specifications in their charters. These boundary denominations may be seen as an attempt by the state at gradually organising the donated lands in such a way that there remained no chance for encroachment of any other plot by the donee. The essay would also highlight the dominance of d...

7 citations

Journal ArticleDOI
TL;DR: In this article, the authors focus on three ports of the eastern sea-board of India and their interactions with ports in Srilanka and India's south-east coast, respectively.
Abstract: The eastern Indian Ocean could be viewed as a world of flows and connections. This paper focuses on three ports of the eastern sea-board of India and their interactions with ports in Srilanka and i...

4 citations


Cited by
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Dissertation
01 Mar 2014
TL;DR: This paper examined data collected during the salvage of the cargo of a merchant vessel foundered in the Java Sea, by a short inscription in a fragment of a bowl and coins dat-ed to around 970 CE.
Abstract: This thesis examines data collected during the salvage of the cargo of a merchant ves-sel foundered in the Java Sea, by a short inscription in a fragment of a bowl and coins dat-ed to around 970 CE. The wreck’s position indicates that the ship was on her way to the island of Java; the verssel herself belongs into the so called ‘lashed-lug and doweled’, Western Austronesian (‘Malayo-Indonesian’) tradition of boat-building. The surviving cargo ranges from Chinese stonewares and Southeast Asian ceramics to Middle Eastern glassware, tin and lead from –proposedly– the Malay Archipelago, and a wide variety of “smaller finds”, most of which can be attributed to the broader area of the western Indian Ocean. The find palpably demonstrates the far-reaching and well-institutionalised trade rela-tions throughout early medieval Asia. It is often assumed that pre-modern Asian com-merce was largely organised in small-scale ventures, the so called “pedlar trade”, and a number of sources indicate structural features of the ships facilitating this commerce that could have supported such a “particularised” exchange. However, a critical assessment of the composition and distribution of the ship’s payload and a virtual reconstruction of the ship and her initial loading pattern reveal that the vessel’s ceramic cargo in all probability was not acquired, handled, and bound to be marketed as a particularised “peddling” ven-ture, but managed by a single authority. The huge amount of ceramics carried on the ves-sel raises questions regarding frequency, volume and modus operandi of maritime ex-changes in tenth-century Southeast Asia, implying that the ship’s tragic voyage was but an attempt at instituting a virtual monopoly in such trade.

91 citations

Dissertation
31 May 2013
TL;DR: The authors argued that the relationship between the experience of pain and specific physiological mechanisms is best understood as one of type identity and proposed a polyvagal-type identity theory of the mammalian pain face.
Abstract: The mind-body problem is the problem: what is the relationship between mind and body? In this project, I claim that the relationship between the experience of pain and specific physiological mechanisms is best understood as one of type identity. Specifically, the personal experience of pain is an allostatic stress mechanism comprised of interdependent nervous, endocrine and immune operations. In Chapter One, I provide five reasons to prefer type identity theory of mind to dualistic philosophies of mind: it has greater explanatory power; it is more respectful of philosophical and folk intuitions about the causal powers of qualia; it is simpler; it is supported by the causal closure of the physical; and it is continuous with the natural sciences and not separate from them. I describe and challenge four philosophical objections to type identity theory of mind: mental states are excluded; mental states disappear; inverted qualia; and Saul Kripke‟s claim that type identity theory is false because two individuals could have the same mental state while having different physiological states. In Chapter Two, I advance a type identity theory of pain supported by a robust theoretical schema as the best description of the mind-body puzzle: what is pain? I frame a well established multilevel descriptive view of the physiological mechanisms that describe pain qualia within the context of advancing theoretical descriptions of the nervous, endocrine and immune systems and their functional interdependencies, and descriptions of allostasis, homeostasis, stress and wounds, all constrained in turn by complex adaptive systems theory. A biological individual is a complex adaptive system coping with a physical and social environment, but possessing nested subsystems. Taken together, these descriptions show how pain qualia are type identified with specific neurophysiological mechanisms; namely: (1) somatosensory qualia of pain, including submodality, intensity, duration and location, are best described as the operations of multisubsystem mechanisms in the neospinothalamic tract; (2) negative emotional pain qualia are the operations of multisubsystem mechanisms in the paleospinothalamic tract; (3) cognitive pain qualia (pain anticipation) are the operations of primary somatosensory cortex (neospinothalamic tract); (4) pain suppression (stress-induced analgesia) are the operations the dorsolateral funiculus pathway and opiate systems (paleospinothalamic tract). The simplest and most parsimonious metaphysical description of these robust relationships is that pain is mechanism. In Chapter Three, I advance a novel polyvagal-type identity theory of pain facial expression to best explain the explanatory mind-body puzzle: how can pain exist? According to some philosophers, assuming neuroscience explains with what mechanistic operations being aware of a burning arm pain is type identical, it is still impossible for any neuroscientific theory to explain how a specific pain must be correlated with a specific mechanism, as opposed to a different mechanism. Thus, there appears to be an explanatory gap. In this chapter, I will attempt to bridge the explanatory gap in two ways. First, based on the theoretical approach for a type identity theory of pain offered in Chapter Two, I offer a polyvagal-type identity theory of the mammalian pain face. I claim type identity theory of mind best explains how the gap can be bridged. Type identity theory of mind makes a realist assumption that pain is causally responsible for behaviours such as facial pain grimaces and screaming. Second, I attempt to bridge the gap by arguing that the supposed gap assumes that type identity theory must reconstruct type pain identities as formal derivations from laws of nature. Based on actual scientific practice and philosophical considerations concerning explanatory levels, I will show that this is a false assumption. Type identity statements that successfully emerge from mechanistic pain explanation are between different delineations of pain phenomena at the same explanatory level; they are intralevel. Although the explanatory gap puzzle correctly shows our incomplete understanding of how pain might be explained by mechanism, the gap merely asserts a practical limit on our present explanatory successes, and is not in principle unbridgeable on a priori grounds, as some philosophers claim. Eliminative materialists also assert that there is nothing more to pain than mechanism, but deny that pain can be type identified with neurophysiological mechanism. The reason is that pain does not really exist. Eliminativists propose that pain is part of folk psychology which consists of false generalizations („wounding is the cause of pain‟) and false theoretical claims ("pain always hurts‟). Thus, pain should be eliminated and replaced by an accurate neuroscientific successor theory. In Chapter Four, I assess philosophical arguments and data for and against eliminative materialism of pain. If eliminativism is correct, then the version of type identity theory of pain I propose in this project is strictly false. While pain folk psychology has stimulated much psychological research resulting in improved clinical outcomes for some pain patients, our own intellectual history reveals that any theory can seem successful even when it is radically false. Neuroscience already shows that many folk pain claims are false, while the truth of many others is not known. Eliminative materialism implies the disquieting consequence that the limit of what can be scientifically eliminated or reduced is much closer than we may conventionally think. Alternately, since intellectual history also offers modest evidence of theoretical co-existence between type identity theory of mind and folk psychology, radical theory change as advocated by eliminativism is just one end-point on a continuum of many possibilities. Still, accommodation such as this cannot change the sobering insight that all human knowledge is ultimately provisional. This realization encourages guarded humility about the ontological status of existing folk and scientific pain theories, including the type identity theory of pain, while it fosters an equally guarded optimism concerning our future theoretical prospects.

32 citations

Journal ArticleDOI
TL;DR: The present data demonstrate that AM 404 evokes a significant hypothermia in rats that is dependent on TRPV1 receptor activation.
Abstract: AM 404 inhibits endocannabinoid uptake and enhances the cannabinoid CB 1 -mediated effects of endogenous cannabinoids. Accumulating evidence also suggests that AM 404 acts at sites other than the endocannabinoid system. One site is the transient receptor potential vanilloid 1 cation channel (TRPV1). A useful endpoint for discriminating between TRPV1- or CB 1 -mediated effects of AM 404 is hypothermia. This is because TRPV1 or CB 1 receptor activation produces a significant hypothermia in rats. The present study investigated the effects of AM 404 (1, 5, 10 and 20 mg/kg, i.p.) on body temperature in rats and the involvement of TRPV1 and CB 1 receptors in the effects of AM 404. Doses of 10 and 20 mg/kg of AM 404 produced significant hypothermia. Pre-treatment with capsazepine (30 mg/kg, i.p.) blocked the hypothermia caused by 10 and 20 mg/kg of AM 404. Pre-treatment with SB 366791 (2 mg/kg, i.p.), a new TRPV1 antagonist, also abolished the hypothermia evoked by AM 404 (20 mg/kg, i.p.). In contrast, pre-treatment with SR 141716A (Rimonabant), a CB 1 antagonist, or AA-5-HT, a fatty acid amide hydrolase (FAAH) blocker, did not affect AM 404-evoked hypothermia. The present data demonstrate that AM 404 evokes a significant hypothermia in rats that is dependent on TRPV1 receptor activation.

31 citations

Journal ArticleDOI
TL;DR: Data indicate that central opioids play a role in the duration of nursing bouts during early lactation, by treating postpartum females with the opioid antagonist naloxone and monitoring their behavioral interactions with pups.

31 citations

Book
01 Jan 1992
TL;DR: A study of the eastern part of the Persian Achaemenid Empire, which was founded around the middle of the sixth century BC by Cyrus the Great, is presented in this article, which draws attention to the nomads from the Central Asia steppes and deserts who throughout history have played a major role in the developments that took place on the Iranian plateau and beyond.
Abstract: A study of the eastern part of the Persian Achaemenid Empire, which was founded around the middle of the sixth century BC by Cyrus the Great. Within 20 years the empire stretched from the Aegean coast in the west, to the Kabul valley in the east. How did the Persians manage to conquer such a vast area within such a short time? And how did they manage to preserve their empire for 200 years before being defeated by the military genius of Alexander of Macedon? The answer to these questions is sought in the chaotic years that preceded the rise of the Achaemenids. On the basis of geographical and general historical information, the Persian Achaemenid texts and reliefs, classical sources and archaeological material, this study draws attention to the nomads from the Central Asia steppes and deserts who throughout history have played a major role in the developments that took place on the Iranian Plateau and beyond.

29 citations